Re-enable @wip chat E2E scenarios quarantined for green CI lane

[mjkatgithub]

Planning

• Milestone: Phase 3
• Priority: P0
• Size: L
• Estimate: 10 SP (split into sub-issues)
• Epic: CI: Fix full lane (coverage + full E2E) #122

Goal

Epic to fix and re-enable the 16 chat E2E scenarios quarantined with @wip
in #122. Each sub-issue covers one cluster with a shared root cause. Remove
@wip per scenario once fixed and green locally.

Quarantine: tests/e2e/scripts/run-cucumber-exclude-email.mjs excludes
@wip; tags in tests/e2e/features/chat.feature.

Sub-issues (suggested order)

1. E2E: Re-enable mobile reply via tap (@wip cluster F) #135 — Cluster F mobile reply via tap (1 SP)
2. E2E: Fix space-home panel hide on channel open (@wip cluster C) #136 — Cluster C space-home panel hide (1 SP)
3. E2E: Fix leave room sidebar button visibility (@wip cluster D) #137 — Cluster D leave room sidebar (2 SP)
4. E2E: Fix member presence away/offline indicators (@wip cluster B) #138 — Cluster B presence away/offline (1 SP)
5. E2E: Fix sidebar unread indicators (@wip cluster A) #139 — Cluster A sidebar unread (2 SP)
6. E2E: Fix E2EE room timeline actions (@wip cluster E) #140 — Cluster E E2EE timeline actions (3 SP)

Definition of done

• All sub-issues closed (user closes after merge)
• No @wip tags remain in chat.feature
• test:ci:full green without @wip exclusion

Branch

Per sub-issue (bug/e2e-wip-*); no single branch for the epic.

Notes

• Split from CI: Fix full lane (coverage + full E2E) #122. Baseline when quarantined: integration 9/9, coverage
  440/440, E2E 29/29.
• Parent tracks progress; implement on sub-issue branches only.
• Docs: N/A at epic level unless a sub-issue moves module boundaries.