feat(i18n): add Simplified Chinese desktop localization - #7777

…est upstream

Merge upstream main at d34c9c2 (163 commits past the PR's base 77729ab)
into the zh-hans follow branch, resolving 26 conflict hunks across 15 files.

Resolution keeps upstream's new functionality and preserves the zh-Hans t()
wrapping:
- effort picker: adopt the rebuilt effortPickerState API (backend/choices,
  note) and translate the new note copy via agents.effort.support-unknown and
  agents.effort.maybe-unsupported
- settings: follow upstream's moderation -> relay-admin section rename; nav
  groups keep both `id` (navGroupLabel / i18n) and the canonical English
  `label` that upstream tests look groups up by
- reportErrorMessage falls back through the catalog (i18n.t), keeping the
  exported signature its tests pin
- community leave hint, huddle confirm, canvas labels, timeout banner: t()
  versions of upstream's new copy
- merged test files keep both the i18n bootstrap and the new upstream cases;
  three upstream test files (ChannelCanvas existence / switch-reset, persona
  model discovery jsdom) gain the standard initializeI18n bootstrap that the
  localized code now needs

Catalog: 5 new entries, en/zh-Hans aligned.
Hardcoded-string baseline: the 150 literals merged in with upstream's new
surfaces (admin console, canvas history, pairing) are triaged as
deferred-pr4-surface with a follow-up wave note — the ready-made backlog for
the next localization pass.

Verified: tsc --noEmit, biome check, px-text, pubkey-truncation, catalog
parity, hardcoded-strings gate, 6876 unit + 139 jsdom tests — all green.

Co-Authored-By: Claude Code <[email protected]>
Signed-off-by: Fizz <537fca8a8c780d947a6ec97425ec282d7307baf48fde373f11824212384c31cb@like.communities.buzz.xyz>

… closes (#9440)

## Summary
`desktop/src/features/terminal/TerminalSubstrate.test.mjs` can pass
every test and then run the Desktop JS job out of memory several minutes
later. This moves the React Testing Library unmount from `beforeEach` to
`afterEach`, so no tree is still mounted when the jsdom window closes.
Only the test file changes (6 insertions, 2 deletions).

Commit (cherry-picked unchanged from a local flake-fix series):
- `test(desktop): unmount every TerminalSubstrate tree before the window
closes`

### CI sighting

One sighting was found in the CI runs from 7 to 12 November 2026 that
were searched:

- 9 November 2026, "Desktop Domain / Desktop JS", run 42706004493
attempt 1 (on #9227; the rerun passed):
-
https://github.com/block/buzz/actions/runs/42706004493/job/129463488242

In that job the suite reported 6,950 of 6,951 passing. The log shows `An
update to TerminalSubstrate inside a test was not wrapped in act(...)`
at 21:54:33Z, then `FATAL ERROR: Ineffective mark-compacts near heap
limit Allocation failed - JavaScript heap out of memory` at 22:02:17Z,
and the file is reported as failed at file level (`test at
src/features/terminal/TerminalSubstrate.test.mjs:1:1`) after 504.6 s.

### Root cause

The file called `cleanup()` only in `beforeEach`, so the last test's
tree was still mounted when `after(() => dom.window.close())` ran. If
ThemeProvider's asynchronous palette update landed after that close, it
re-rendered the substrate, the splash effect's palette guard passed, and
`requestAnimationFrame` on the closed window started a fresh jsdom
interval that nothing cleared. That 60 Hz loop repainted the banner into
the test's recording `getContext` stub indefinitely, and `paintLog` grew
until the heap limit. No individual test hangs, so a per-test timeout
would not catch it.

### Fix

`afterEach(() => cleanup?.())` unmounts every tree, including the last,
before `after()` closes the window. The `beforeEach` call became
redundant and is removed. No assertions change, and no timeouts, retries
or sleeps are added.

### Related issue
N/A (flake fix). No existing issue or PR for this failure was found.
Three open PRs touch the same test file (#5057, #5485, #7777); none of
them changes where `cleanup` runs.

### Testing
Human testing is still required. This PR does not carry
`buzz-review-completed`; the author has not yet run this test themselves
on this branch.

#### Verification of the fix (before this branch was split out)
- The test file, 5 consecutive runs: 25 of 25 tests passed each time in
about 6.8 s, with no `act` warning.
- The CI out-of-memory failure was not reproduced with the real test
file. Its mechanism was reproduced in a scratch harness with the same
stubs: without cleanup before the window close, 3 of 3 runs left the
palette unresolved at close, added 11,556 `paintLog` entries per 100 ms,
kept one live timer, and never exited. With cleanup before the close, 3
of 3 runs added no entries, left no timers, and exited on their own.

#### Local checks on this branch
The push ran the repository's full pre-push hook set from a checkout of
this branch's head (`7f4117340`), with no lanes excluded and without
`--no-verify`. The branch is one commit behind `main`; that commit
changes only mobile and docs files, none of them touched here.

Ran and passed:
- `branch-skew`, `push-head-scope` and `file-size-check`
- `desktop-check` (`pnpm check`)
- `desktop-typecheck` (`pnpm typecheck`)
- `desktop-test` (`pnpm test`, the full desktop unit suite, which
includes `TerminalSubstrate.test.mjs`)

Did not run:
- `rust-tests`, `desktop-tauri-checks` and `mobile-checks`. The hook
selects lanes by changed path, and this branch changes no Rust, Tauri or
mobile file.
- Desktop builds and the Playwright E2E suites, which are CI-only.
- `just ci`.
- The 5-run repetition and the scratch harness above were not repeated
on this branch.

A green run does not prove the flake is gone: the failure needs the
palette update to land after the window closes.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Signed-off-by: mtoohey <[email protected]>
Signed-off-by: Matt Toohey <[email protected]>
Co-authored-by: Claude Fable 5.1 <[email protected]>