…mate (erigontech#21667)

## Summary

Fixes a parallel-exec OCC correctness bug: the apply loop was flushing
writes from txs that **failed validation** (`VersionInvalid`) with the
`complete=Done` flag, leaking phantom committed state into the
versionMap
where downstream readers picked it up.

## Symptoms before this fix

- **Intermittent wrong-trie-root failures** during from-genesis parallel
  sync (PR erigontech#21591 made `EXEC3_PARALLEL=true` the default).
- **Pattern-2 family**: gas-mismatch failures on DEX strategy contracts,
  especially in the gnosis 14.8M-18.5M block range.
- **Cascading mis-execution**: a phantom write at tx[N] is picked up by
  tx[N+k] via `MapRead`. Version-only validation passes because
`readVersion == writtenVersion`. The downstream tx commits state derived
from the phantom, and the divergence surfaces as a gas-mismatch tens of
  thousands of blocks later.

Captured deterministically at gnosis block **18,483,405**: tx[3] inc=0
was flagged Invalid by `ValidateVersionBlock`, but its 28 writes were
flushed with `complete=true` because `cntInvalid == 0` (the counter only
tracks *prior* `VersionTooEarly` txs). Slot 0x08 on contract
`0x18b2b7673c6d661923e9460d592699617828b293` was stored with value
`aabS...5981`. tx[16] subsequently read that phantom via `MapRead` and
committed phantom-derived state. The cascade surfaced as a gas-mismatch
roughly 80K blocks downstream.

## Fix

New helper `applyLoopFlushAsComplete(valid, cntInvalid) = valid &&
cntInvalid == 0`
gates the `complete` flag. An invalidated tx now flushes as
**Estimate**,
which causes downstream reads of those cells to return
`MVReadResultDependency`. The validator treats that as `VersionInvalid`,
forcing the dependent tx to re-execute after the retry settles -
restoring
OCC's \`Done = committed\` invariant.

Companion clarity changes in the same files:

- \`exec3_parallel.go\`: read \`txVersion\` from
\`txResult.Task.Version()\`
(the \`*taskVersion\` wrapper that carries the current \`Incarnation\`)
instead of bare \`TxTask\` which always returns \`Incarnation=0\`. Logs
  and traces now show the correct incarnation on retries.
- \`txtask.go\`: drop the dead \`TxTask.Incarnation\` field. Live source
of
truth is the \`txIncarnations\` counter plus the \`taskVersion\`
wrapper.

## Verification

- **Unit tests**
(\`execution/stagedsync/exec3_parallel_robustness_test.go\`):
  - \`TestApplyLoopFlushAsComplete\` - 4-case truth-table on the helper,
including the regression guard case "INVALID current tx -> must NOT be
Done".
  - \`TestApplyLoopFlush_InvalidTxWritesAreEstimate\` - drives the
    production helper through a real \`VersionMap\` using the gnosis
    18,483,405 contract+slot, asserts downstream read returns
    \`MVReadResultDependency\` (not \`MVReadResultDone\`).
  - Both confirmed to FAIL with the helper temporarily reverted to
    \`cntInvalid == 0\`, PASS with the fix.

- **Gnosis oracle CHECK** (live): swept blocks **18.46M-18.70M+
end-to-end**
  with zero \`STATE-ORACLE-DIVERGENCE\` events, zero gas-mismatch, zero
  wrong-trie-root.

- **From-genesis resync** (live): currently past historical fail blocks
  **14,837,280 / 14,845,967 / 16,420,113** without recurrence; still in
  progress through the rest of the 14.8M-18.5M range.

## Milestone

**Needs to be merged before 3.5 is cut.** With PR erigontech#21591 making
\`EXEC3_PARALLEL=true\` the default on main, this bug class affects all
3.5+ users running parallel execution. Marked for the 3.5.0 milestone.

## Test plan

- [ ] CI green
- [ ] Reviewer checks the helper's truth-table covers all four
      \`(valid, cntInvalid)\` cases
- [ ] Reviewer confirms the \`MVReadResultDependency\` -> validator
      -> re-exec path closes the OCC invariant

---------

Co-authored-by: yperbasis <andrey.ashikhmin@gmail.com>

…21687)

Addresses code→docs gaps found in weekly maintenance run w24, plus some
Fundamentals housekeeping. **Scope: release/3.5 only.**

### Flags & env vars (`configuring-erigon`)
- Add `--snap.chaintoml-url` flag (PR #21584), including
`ERIGON_REMOTE_PREVERIFIED` override precedence
- Add `--snap.p2p-manifest` flag (PR #20526), tagged *(New in v3.5)*
- Update `EXEC3_PARALLEL` default to `true` (PR #21591)
- Add `--exec.serial` and `--exec.no-prune` flags (new in v3.5); also
document `--exec.batched-io` and `--exec.state-cache`
- Document `--exec.workers`. Its effective default is the **full
CPU-core count** (inherited from the `EXEC3_WORKERS` fallback when the
flag is unset); the flag's own `--help` text says "half the CPU cores",
which is a known inconsistency in the binary

### Prune modes / snapshots
- Update `pruning-modes.md` with the EIP-8252 retention-window breaking
change (v3.5): full mode now prunes block bodies/receipts to the last
262,144 blocks (previously kept all post-merge blocks) and will stop
serving older block/receipt data; state-history window grows 100k→262k
- Add new "Snapshots Management" page under Fundamentals (`seg du`,
snapshot categories, node-type estimates, EIP-8252 retention window).
The `seg du` example uses an archive datadir, since the estimator only
sums on-disk files and the archive row therefore equals the current
total
- Fix the `erigon snapshots …` ver-format upgrade/downgrade commands in
`get-started/installation/upgrading.md`

### Fundamentals section housekeeping
- Fix a Mermaid parse error on the **Architecture** page — the
Caplin→Execution edge label had unquoted parentheses (`|new
blocks<br/>(Engine API)|`), which the flowchart parser rejects; now
quoted
- Reorder the Fundamentals sidebar into a clean integer reading order.
It had grown to ~23 entries with colliding `sidebar_position` values and
scattered related pages. New order: concepts first (Architecture,
Database, Pruning Modes, Snapshots Management, Caplin) → configuration →
operations/tuning → security → integrations
- **NAT** moved out of the CLI Reference subfolder to a top-level
Fundamentals page (next to Default Ports):
`/fundamentals/configuring-erigon/nat` → `/fundamentals/nat`. The old
URL is preserved via a client-side redirect
(`@docusaurus/plugin-client-redirects`, pinned to 3.10.0); the site is
on GitHub Pages, which can't do host-level 301s
- The **CLI Reference** page was flattened
(`configuring-erigon/index.mdx` → `configuring-erigon.mdx`); its
`/fundamentals/configuring-erigon` URL is unchanged

### Mobile UI
- Adds a theme-color meta tag to the docs site so mobile browsers tint
the address/status bar with the Erigon brand orange — the same behavior
the main website, Cocoon and Zilkworm docs already have.

Regenerated `llms.txt` / `llms-full.txt` artifacts.

---
_Updated after Copilot + @yperbasis review: replaced the `seg du`
example with **real mainnet-archive output** (correct ByteCount
renderings, `extensions:` line, byte-exact estimates table); documented
`other_extensions`; made `--datadir` optional and chain-agnostic;
clarified full-mode block-pruning impact; corrected the `--exec.workers`
default and tagged all `--exec.*` flags as new in v3.5; added
`--exec.batched-io` / `--exec.state-cache`; fixed the RPC cert filename
typos in **TLS Authentication** (`RPC key.pem` → `RPC-key.pem`,
`RPC.crtv` → `RPC.crt`); gave NAT an integer sidebar position and moved
the **Modules** overview first; removed a stray editorial note in the
CLI reference; typed the `seg du` code fences as `text`; de-duplicated
pruning-mode concepts on the Snapshots page (now deferring to
`pruning-modes.md`); and fixed `sidebar_position` collisions._

---------

Co-authored-by: Andy (NanoClaw) <andy@nanoclaw.ai>
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>
Co-authored-by: Bloxster <gianni.morselli@erigon.tech>