feat(cloud): complete managed collaboration epic

[Neonforge98]

Summary

• Adds the ORGII Cloud endpoint and authentication flow, cloud organizations, membership, roles, invites, quotas, presence, and realtime reconciliation.
• Adds team-session publishing, directed sharing, share-link import, remote-session browsing, blame navigation, comments, per-round threads, address-comments agent tasks, revoke, delete, and fork/continue flows.
• Adds bidirectional Project and Work Item synchronization with durable outbox handling, conflicts, locks, tombstones, ownership transfer, member removal, and local Personal-scope isolation.
• Adds import and fork support for local external agent histories, including Codex, Claude Code, Cursor, OpenCode, Windsurf, WorkBuddy, Trae, Cline, Warp, and ZCode.
• Adds instance-profile build/open tooling plus rendered dual-instance E2E coverage for the cloud collaboration matrix.

Change shape

• One feature commit on top of the latest develop.
• 497 changed files: 188 added, 284 modified, 25 deleted.
• 62,059 insertions and 8,320 deletions.
• 95 test files and one canonical architecture document; obsolete collaboration paths and setup SQL embedded in the app are removed.
• The managed-encryption hardening currently under design is intentionally not included here and remains in a local stash.

Validation

• ✅ pnpm typecheck
• ✅ pnpm lint
• ✅ git diff --check
• ✅ Updated imported-history provider registry test: 5/5
• ⚠️ Full Vitest run before the stale ZCode expectation was fixed: 5121/5125 passed. Of the remaining failures, the chat-tab timeout passed on an isolated rerun; settings parity for housekeeper.features.contextCompact and the null editUtils case are unchanged from current develop.
• ⚠️ cargo check --workspace reaches the e2e-test crate, then fails in current develop because crates/e2e-test/src/housekeeping.rs references the missing seed_aged_file helper. This branch does not change that file.

Review guide

1. Cloud auth, endpoint, and organization management
2. Session share, import, comments, address-comments, fork, and blame UX
3. Project and Work Item cloud bridge and conflict behavior
4. Rust collaboration bridge and session provenance
5. Dual-instance E2E harness and rollout tooling

Rollout notes

The matching ORGII Cloud database schema must be deployed before enabling the feature against a hosted endpoint. Keep this PR as Draft until the inherited develop CI failures are resolved and the final hosted dual-instance acceptance pass is recorded.