[pascalandr]

Summary

• Add General → Automatically expand subsessions, enabled by default.
• A visible collapsed row opens paths to active descendants on a new working,
  compacting or permission/form-input chevron state, if it is selected or is a
  descendant of the selected conversation. The rule applies recursively at any
  depth. Other families keep their activity indicators without opening.
• Pointer position is irrelevant. Collapsing a busy branch, scrolling a busy row
  into view or enabling the setting alone does not trigger expansion.
• Delete the manual-collapse suppression map and the distinction between manual
  and automatic expansion in saved state. All open branches restore normally.

Implementation

SessionList observes the underlying descendant activity kind independently of
expansion and preferences, checks actual scroll-viewport visibility (including
Virtua's buffered offscreen rows), then asks revealSubsession to open the paths
below the selected conversation. Status setters and metadata reads no longer
open branches directly. Local reveal authority protects expansion against late
snapshot hydration, using the same state as manual expansion.

Validation

• UI typecheck: passes.
• Store/recovery/client-state/i18n checks: 179/179 pass.
• Updated recursive browser tests: 5/5 pass (session-child-activity and session-search).
• Final local browser run on the rebased PR revision: 62/62 pass, covering
  recursive expansion, search/selection, Electron/Tauri project restoration,
  deletion, native Preferences and fixture wiring across six browser files.
• Help checks: 31/31 pass; messages and help updated in all ten locales.
• Separate Electron dev instance tried by the user; General preference toggling
  verified against the real backend.

Large touched source files

Under packages/ui/src: components/session-list.tsx (~1,070 lines),
stores/preferences.tsx (~1,619), stores/session-state.ts (~1,336),
stores/session-events.ts (~720), and the ten lib/i18n/messages/*/settings.ts
files (~764–778 each). This change keeps them in place and removes the extra
expansion bookkeeping.

[pascalandr]

Gatekeeper review — round 1

Result: no P0–P2 findings; no concrete P3 defects identified at 6ab189b7b.

Verified

• Deferred activity observation avoids mount, selection, preference and collapse
  retriggers. Visible leaves remain subscribed when their first child appears.
• Production list props and revealSubsession share the same per-tab selection.
• Persistence retains manual-close authority and deletion fences while saving
  automatic and manual expansions alike.
• General preference wiring, messages and help cover all ten locales.
• Focused store tests: 5/5 pass. UI typecheck: passes.

Browser regressions and full CI are tracked separately on the PR.

Large touched sources under packages/ui/src/: components/session-list.tsx
(~1,070 lines), stores/preferences.tsx (~1,619), stores/session-state.ts
(~1,336), stores/session-events.ts (~720), and the ten
lib/i18n/messages/*/settings.ts files (~764–778 each).

[pascalandr]

Full CI follow-up

The full workflow is not green. The three session-expansion browser scenarios
all passed in CI (collapsed-chevron activity, recursive visible branches/settings/
restoration, and buffered offscreen rows). Local final browser validation was 62/62.

Compared the failed logs from this run
(41372632395)
with the preceding #1264 run
(41368136045).
Both runs contain the same failures:

• permissions/receipts.test.ts: expected 204, received 503.
• workspaces/git-requirement.test.ts: expected 200, received 503 with
  Mission schedule carrier ownership could not be verified; also fails on
  Windows, macOS and Ubuntu compatibility jobs.
• mission-scheduling.test.ts: startup path.join receives undefined.
• automation-forms.test.ts: creation/request-count assertions (including 5 vs 1).
• mission-lifecycle-revision.test.ts: the Pause/form-work assertion, 0 vs 1.

An additional mission-control.test.ts timeout waiting for the Resume control
at line 1088 did not appear in that preceding run. Browser shard 2 alone has
been rerun to check it. No unrelated source changes or blanket retries were made.

[pascalandr]

Follow-up: browser shard 2 passed on rerun. The additional mission-control Resume-control timeout did not recur. The session-expansion scenarios passed in the original CI run; the remaining failures are those also observed in the preceding #1264 run, documented above. Full CI remains red because of those outstanding failures.