Closes #2495.

Summary

Adds ui/src/ui/app.smoke.test.ts — a smoke test that instantiates the real RemoteClawApp Lit class via document.createElement("remoteclaw-app") and asserts every required field of LifecycleHost, GatewayHost, and ToolStreamHost is defined on the fresh instance.

Problem this defends against

The gateway-disconnect regression in #2493 shipped because:

• All existing app-*.node.test.ts fixtures construct synthetic plain-object hosts that happen to match the three host interfaces.
• Zero tests instantiated the actual RemoteClawApp class.
• TypeScript assertions on this as unknown as Parameters<typeof fn>[0] (cast through unknown) erased the structural check between the class and the host types.

Result: fixtures passed, class was missing connectGeneration/serverVersion/chatStreamSegments, gateway connect silently broke, no test caught it.

Approach

• Import ./app.ts once → registers the remoteclaw-app custom element via @customElement decorator
• document.createElement("remoteclaw-app") → instantiates the real class (runs all property initializers)
• Three it blocks — one per host interface — assert every required field is !== undefined
• Field lists are enumerated statically from each host interface's required (non-optional) members; optional fields (client?, connected? in LifecycleHost; onboarding? in GatewayHost) are correctly excluded

as unknown as Record<string, unknown> cast (not as any — typescript/no-explicit-any is an oxlint error per .oxlintrc.json) enables dynamic field access without type-safety loss at the boundary we're testing.

Acceptance criteria verification

• New file ui/src/ui/app.smoke.test.ts exists — 105 LOC
• Test asserts every required field of LifecycleHost (18), GatewayHost (31), ToolStreamHost (9)
• Test PASSES on current HEAD (3 / 3 green)
• Test FAILS if any restored field is removed — verified interactively for all three:
  • Removing serverVersion → 2 test failures (Lifecycle + Gateway)
  • Removing chatStreamSegments → 1 failure (ToolStream)
  • Removing connectGeneration → 1 failure (Lifecycle)
• Test runs under the existing Playwright browser config (ui/vitest.config.ts) — the superset of the JSDOM environment the issue contemplated; no separate JSDOM plumbing was added
• No Playwright-specific APIs used — the test only needs document.createElement and standard custom-element registration, and would run identically under a JSDOM config if one existed
• tsgo clean, oxfmt --check clean, oxlint --type-aware clean

Out of scope (future follow-ups)

The issue mentions a "stronger variant" that auto-derives the field list from the TypeScript interface via tsc --emitDeclarationOnly or type introspection. That would close the gap permanently (new host-interface fields auto-asserted without test updates). Explicitly deferred in the issue — worth a follow-up once this lands.

References

• Defends against the regression class fixed in fix(ui): restore connectGeneration/serverVersion/chatStreamSegments on RemoteClawApp — gateway connect silently broken #2493
• Complements refactor(ui): remove as unknown as Parameters<typeof X>[0] casts — restore structural type-checking #2494 (cast removal eliminates the type-erasure that hid the bug)
• Extends naturally to cover findings from audit(ui): missing field initializers across PollingHost/ChatHost/SettingsHost/ScrollHost/CompactionHost on RemoteClawApp #2496

🤖 Generated with Claude Code