* docs(swim-37): `lich` primitive wiring memo (memo-before-wire)

Decides shape for `captureSwim("lich", …)` before the wiring PR per
🩸's memo-before-wire standard. Maps the harness label `lich` to the
post-compaction-delegate release seam (`emitContinuationCompactionReleasedSpan`).

Resolves four design Qs:
  Q1 (timers): N/A — release helper is synchronous.
  Q2 (releasedCount): cover non-empty (production-typical) AND empty
    (defensive helper-clamp, NOT production-reachable). Pin both.
  Q3 (compaction.id): three cases — present+valid / omitted / invalid.
    Helper drops-with-log on invalid; integration-tier verifies via
    log-callback substring match.
  Q4 (drained_count): adjacent axis NOT in scope (different seam).

Proposes 6 live integration-tier tests, no separate helper-tier file
needed (integration coverage pins the helper-tier invariants through
the public surface).

Open Q deferred: cross-primitive chain-id-propagation lifecycle test
(continue_delegate post-compaction → lich release) deserves its own
primitive and memo.

Boundary discipline preserved from #405/#407/#410: STDOUT-only,
in-memory recorder, try/finally reset, no silent defaults,
snapshot-at-emit.

Refs #324
Companions:
  - docs/design/swim-37-continue-delegate-wiring-memo.md (🌻, #405)
  - swim-37 `heartbeat` memo (🌻, in flight)

* docs(swim-37): pin NaN/Infinity for compaction.id invalid path (🌊 #411 review)

Per 🌊's review on #411: extend Q3 invalid-path test list to include
`NaN` and `Infinity` alongside `-1` and `1.5`. Same defense-parity
shape as #405's `recipients` positive-integer validation.

`Number.isInteger(NaN) === false` and `Number.isInteger(Infinity) === false`,
so the existing helper guard already catches both — pinning them
observably rather than leaving the invariant implicit.

* docs(swim-37): fix test-count headers (six → eight) per 🌻 #411 nit

Header at "Proposed test list" still said six; helper-tier-vs-integration-tier
section still said "6 live tests". Both updated to eight to match the
NaN/Infinity additions from d5cf713.

Memo-before-wire pattern (per #405's continue_delegate memo at
3bb086c762, endorsed by figs's 'measure thrice, cut 1x').

Defines:
- Production span shape: name 'heartbeat' (bare, not 'continuation.heartbeat'),
  signal.kind+heartbeat.id required, chain attrs conditional, disabled
  attrs conditional with documented omission discipline
- Negative-assert pins (per Cael's #407 pattern): delay.ms and
  chain.step.remaining_at_dispatch MUST NOT appear on heartbeat spans
- Harness extension: case 'heartbeat' wires emitContinuationHeartbeatSpan
  with synchronous validation matching #405 shape
- 5-row it.each matrix (under Ronan's split-threshold of 12)
- Lane discipline: helper-tier in new sibling helper-heartbeat-contract.test.ts;
  integration-tier extends swim-runner.test.ts

Open Qs for cohort sign-off:
- Q1: heartbeat-with-no-continuation-context emit/skip (lean: continuation-gated
  for production, always-emit for harness — divergence documented in README)
- Q2: heartbeat.fire sibling? (lean: no, single span; lag becomes attribute)
- Q3: 5-row matrix shape (under split-threshold)
- Q4: in-PR helper vs separate issue (lean: in-PR, new helper not new axis)

Companion to:
- docs/design/swim-37-continue-delegate-wiring-memo.md
- silas/swim-37-lich-memo (in flight)

Refs #324.

…ionHeartbeatSpan helper (#412) (#417)

Memo-before-wire fold from #412 (merged at `1b84e71c95`). Stacks on
`cael/325-canonical2` between #414 (lich wire) and #416 (rebase.classify wire).

Surface additions to `src/infra/continuation-tracer.ts`:
- New helper `emitContinuationHeartbeatSpan({ heartbeatId?, chainId?,
  chainStepRemaining?, disabledReason?, log? })` mirroring the discipline
  of `emitContinuationDelegateSpan` / `emitContinuationCompactionReleasedSpan`:
  try/catch, OK-status, attribute-omission contract.
- `heartbeat.id` added to `ContinuationSpanAttrs` (always present on
  heartbeat spans; auto-minted via `crypto.randomUUID()` when caller omits).
- `"heartbeat"` added to `CONTINUATION_SIGNAL_KINDS` SSOT.
- `ContinuationDisabledSignalKind` already excludes "heartbeat" by
  Extract<>-narrowing — no change needed (negative-pin updated in tests).

Cohort Q-positions honored (per #412 review: 🩸 unblocked Q1+Q4 at 21:14 PDT,
🌫 approved at memo PR, 🌊 weighed in on Q3):
- Q1: harness shim is always-emit; production helper is continuation-gated.
  Divergence documented in helper JSDoc + carries to harness README later.
- Q2: single `heartbeat` span (NO sibling `heartbeat.fire`); future
  `heartbeat.lag.ms` becomes an attribute, not a sibling span.
- Q3: 5-row `it.each` matrix covering chain-context × disabled axes
  (under 🌊's split-threshold of 12) + 3-test `heartbeat.id` provenance
  describe block. Total +13 live tests, -2 `it.todo`.
- Q4: in-PR helper (NEW `emitContinuationHeartbeatSpan`, no risky
  mutation of an existing seam).

Negative-assert pins (per memo §2 + 🩸's #407 negative-pin pattern):
- `delay.ms` MUST NOT appear (heartbeats fire on cadence, not
  caller-elected delay).
- `chain.step.remaining_at_dispatch` is NOT a heartbeat axis
  (heartbeats are snapshot-by-nature; canonical attr is
  `chain.step.remaining`).
- Both pinned via `expect("<attr>" in attrs).toBe(false)`
  belt-and-braces beyond `toBeUndefined()`.

Tests:
- `pnpm vitest run src/infra/continuation-tracer.test.ts studies/swim-37/harness/swim-runner.test.ts`
  → 108 passed / 11 todo (was 95 passed / 13 todo for these two files).
- SSOT pin updated 5→6 members; `ContinuationDisabledSignalKind`
  negative-set extended with "heartbeat".

Lane discipline: zero overlap with #414 (`lich`), #415 (`chain.id`
absence pin on lich), or #416 (`rebase.classify` in NEW `src/rebase/tracer.ts`).

Co-authored by 🌫 / 🌊 / 🩸 via memo Q-positions on PR #412.

…407)

Adds studies/swim-37/harness/helper-fire-and-release-contract.test.ts
covering the four landed Slice-2 emit helpers that 🌊's #406 helper-tier
file did NOT cover: chunks 5b (continuation.delegate.fire), 5c
(continuation.work.fire), 6a (continuation.queue.drain), and 6b
(continuation.compaction.released).

Layering: HELPER-TIER ONLY. Drives src/infra/continuation-tracer emit
helpers directly through the InMemorySpanRecorder shim (#394) and asserts
recorded span CONTRACT. Does not touch agent-runner / pi-embedded-runner /
subagent-announce — the runtime callsites are exercised through the
integration tier in swim-runner.test.ts (🌻's #405 captureSwim shim).

LANE-CLEAN: original swim-runner.test.ts is untouched here (avoiding
collision with #405 which converts swim-runner it.todos in-place).
Companion to 🌊's #406 emit-helper-contract.test.ts (which covers chunks
3/4/6c) — same layer, different spans, zero overlap.

Key contract pin per 🩸's lane-clear note (msg 1498508045725204500): the
snapshot semantic for fire spans lives in the PARAMETER name
(chainStepRemainingAtDispatch) and the docs; emitted attr stays canonical
chain.step.remaining. We negative-assert chain.step.remaining_at_dispatch
is NEVER present so a future helper change can't silently invent it.

Coverage:
- continuation.compaction.released (#397): exactly-once emit, signal.kind
  + integer compaction.released, compaction.id valid path,
  validate-and-drop-with-log on invalid (chunk 6c §B + #401)
- continuation.queue.drain (#395): integer count attrs, defense-in-depth
  cap on continuation subset (per 🩸 #395 byte-walk)
- continuation.delegate.fire (#388 chunk 5b): persisted chain.id +
  canonical attr names + negative-assert .at_dispatch absent;
  fire.deferred_ms integer-floor + drift formula; reason.preview 80-char
  truncation + omission
- continuation.work.fire (#388 chunk 5c): canonical attr name (5c
  symmetric to 5b minus delegate.* attrs); no continuation.disabled
  sibling (chunk 5c scope); chainId-invariant violation no-ops + logs
  without throwing

Tests: 12 (all live, no it.todo). Lint clean.

Refs: #324 #334 #388 #395 #397 #401 #394 #406 (sibling) #405 (sibling)

* docs(swim-37): `lich` primitive wiring memo (memo-before-wire)

Decides shape for `captureSwim("lich", …)` before the wiring PR per
🩸's memo-before-wire standard. Maps the harness label `lich` to the
post-compaction-delegate release seam (`emitContinuationCompactionReleasedSpan`).

Resolves four design Qs:
  Q1 (timers): N/A — release helper is synchronous.
  Q2 (releasedCount): cover non-empty (production-typical) AND empty
    (defensive helper-clamp, NOT production-reachable). Pin both.
  Q3 (compaction.id): three cases — present+valid / omitted / invalid.
    Helper drops-with-log on invalid; integration-tier verifies via
    log-callback substring match.
  Q4 (drained_count): adjacent axis NOT in scope (different seam).

Proposes 6 live integration-tier tests, no separate helper-tier file
needed (integration coverage pins the helper-tier invariants through
the public surface).

Open Q deferred: cross-primitive chain-id-propagation lifecycle test
(continue_delegate post-compaction → lich release) deserves its own
primitive and memo.

Boundary discipline preserved from #405/#407/#410: STDOUT-only,
in-memory recorder, try/finally reset, no silent defaults,
snapshot-at-emit.

Refs #324
Companions:
  - docs/design/swim-37-continue-delegate-wiring-memo.md (🌻, #405)
  - swim-37 `heartbeat` memo (🌻, in flight)

* docs(swim-37): pin NaN/Infinity for compaction.id invalid path (🌊 #411 review)

Per 🌊's review on #411: extend Q3 invalid-path test list to include
`NaN` and `Infinity` alongside `-1` and `1.5`. Same defense-parity
shape as #405's `recipients` positive-integer validation.

`Number.isInteger(NaN) === false` and `Number.isInteger(Infinity) === false`,
so the existing helper guard already catches both — pinning them
observably rather than leaving the invariant implicit.

* docs(swim-37): fix test-count headers (six → eight) per 🌻 #411 nit

Header at "Proposed test list" still said six; helper-tier-vs-integration-tier
section still said "6 live tests". Both updated to eight to match the
NaN/Infinity additions from d5cf713.

…ionHeartbeatSpan helper (#412) (#417)

Memo-before-wire fold from #412 (merged at `1b84e71c95`). Stacks on
`cael/325-canonical2` between #414 (lich wire) and #416 (rebase.classify wire).

Surface additions to `src/infra/continuation-tracer.ts`:
- New helper `emitContinuationHeartbeatSpan({ heartbeatId?, chainId?,
  chainStepRemaining?, disabledReason?, log? })` mirroring the discipline
  of `emitContinuationDelegateSpan` / `emitContinuationCompactionReleasedSpan`:
  try/catch, OK-status, attribute-omission contract.
- `heartbeat.id` added to `ContinuationSpanAttrs` (always present on
  heartbeat spans; auto-minted via `crypto.randomUUID()` when caller omits).
- `"heartbeat"` added to `CONTINUATION_SIGNAL_KINDS` SSOT.
- `ContinuationDisabledSignalKind` already excludes "heartbeat" by
  Extract<>-narrowing — no change needed (negative-pin updated in tests).

Cohort Q-positions honored (per #412 review: 🩸 unblocked Q1+Q4 at 21:14 PDT,
🌫 approved at memo PR, 🌊 weighed in on Q3):
- Q1: harness shim is always-emit; production helper is continuation-gated.
  Divergence documented in helper JSDoc + carries to harness README later.
- Q2: single `heartbeat` span (NO sibling `heartbeat.fire`); future
  `heartbeat.lag.ms` becomes an attribute, not a sibling span.
- Q3: 5-row `it.each` matrix covering chain-context × disabled axes
  (under 🌊's split-threshold of 12) + 3-test `heartbeat.id` provenance
  describe block. Total +13 live tests, -2 `it.todo`.
- Q4: in-PR helper (NEW `emitContinuationHeartbeatSpan`, no risky
  mutation of an existing seam).

Negative-assert pins (per memo §2 + 🩸's #407 negative-pin pattern):
- `delay.ms` MUST NOT appear (heartbeats fire on cadence, not
  caller-elected delay).
- `chain.step.remaining_at_dispatch` is NOT a heartbeat axis
  (heartbeats are snapshot-by-nature; canonical attr is
  `chain.step.remaining`).
- Both pinned via `expect("<attr>" in attrs).toBe(false)`
  belt-and-braces beyond `toBeUndefined()`.

Tests:
- `pnpm vitest run src/infra/continuation-tracer.test.ts studies/swim-37/harness/swim-runner.test.ts`
  → 108 passed / 11 todo (was 95 passed / 13 todo for these two files).
- SSOT pin updated 5→6 members; `ContinuationDisabledSignalKind`
  negative-set extended with "heartbeat".

Lane discipline: zero overlap with #414 (`lich`), #415 (`chain.id`
absence pin on lich), or #416 (`rebase.classify` in NEW `src/rebase/tracer.ts`).

Co-authored by 🌫 / 🌊 / 🩸 via memo Q-positions on PR #412.