The GHCR image was built only for linux/amd64, forcing Apple Silicon and
ARM server users into slow QEMU emulation. Add setup-qemu-action and
build for linux/amd64,linux/arm64 so the manifest list covers both.

…ndex (#254)

#249 reported four defects on a 4.11.0 install. Two reproduce on master:

A. os.replace fails with WinError 5/32 while an antivirus, indexer or
   concurrent reader holds the destination or the source without
   FILE_SHARE_DELETE. Checkpoint writes swallowed it as non-fatal, and the
   final metadata save aborted the reindex. replace_with_retry() retries
   only those two codes for about 1.5 s, then re-raises the original
   error. It now backs every atomic replace: metadata, checkpoint, repair
   journal, FTS5 state and staged documents. Other platforms are unchanged.

C. reindex_documents answered "started" while a watcher pass or a
   document write held the index lock, and index_all then refused the run
   at once. start_reindex_background now probes the lock and returns the
   existing already_running envelope. nuclear_rebuild still starts,
   because it waits for the lock instead of refusing.

docs/API.md now says which operations make reindex_documents answer
already_running. The Windows test declares CloseHandle types so a 64-bit
HANDLE is not truncated.

B and D do not apply upstream: reindex_state.json, _write_reindex_state
and a per-document metadata flush are not in any published release, and
_maybe_persist_checkpoint already checks the 500-docs/30-s cadence before
it saves.

Closes #249

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

Patch release. Fixes the startup crash on every fresh install and every
new data directory since v4.10.0 (#248, #252), makes state-file writes
robust on Windows and stops reindex_documents from reporting a refused
run as started (#249). Also ships #236 and the multi-arch Docker image
from #242.

- pyproject.toml: 4.11.0 -> 4.11.1
- mcp_server/__init__.py: __version__ -> 4.11.1
- npm/package.json: 4.11.0 -> 4.11.1
- CHANGELOG.md: Unreleased promoted to v4.11.1 with highlights and credits
- .github/api-surface-baseline.json: regenerated with --snapshot. Additive
  only: 8 modules and 5 methods added since the 2026-08-10 snapshot, none
  removed.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

Updates the requirements on [pre-commit](https://github.com/pre-commit/pre-commit) to permit the latest version.
- [Release notes](https://github.com/pre-commit/pre-commit/releases)
- [Changelog](https://github.com/pre-commit/pre-commit/blob/main/CHANGELOG.md)
- [Commits](pre-commit/pre-commit@v4.6.2...v4.7.0)

---
updated-dependencies:
- dependency-name: pre-commit
  dependency-version: 4.7.0
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <support@github.com>