Rel.AI MCP 0.21.9

Tool-call latency overhaul

• Read-only tools now share a per-workspace reader/writer lock instead of serializing behind the mutation queue, so a batch of relai_read, relai_search, relai_status, or relai_diff calls dispatched together runs concurrently while edits stay exclusive.
• Session-history writes use a prune fast-path and parsed-session cache, while history listings revalidate high-resolution file metadata so updates from the desktop app, connector server, or another process cannot remain stale.
• The workspace tree walk dropped one realpath syscall per file, taking relai_repo_snapshot and relai_code_inspect collection from ~70-94 ms to ~7 ms on a 350-file repository.
• relai_code_inspect gained per-file identifier and token sets so symbol, references, and related queries skip files that cannot match: warm queries went from ~102-124 ms to ~13-19 ms.
• config.json is parsed once per change instead of once per tool call, workspace root realpaths are memoized, and command discovery plus validation-check detection now share a manifest-signature cache.
• relai_repo_snapshot overlaps its git summary with the tree walk, and relai_git_commit overlaps its work-tree probe with the status read. relai_diff deliberately waits for canonical status classification before reading any diff so sensitive paths are never loaded speculatively.
• relai_read accepts ranges:[{path,startLine,endLine}] so several files with different line windows resolve in one call instead of one call per file (tool surface version 12).
• relai_status skips the package.json read and .github/workflows CI scan for connector calls, which strip both from the result anyway.
• Git status consumers now share NUL-delimited porcelain parsing, preserving filenames with spaces and non-ASCII characters across review, status, baseline ownership, tidy, and command mutation tracking. Unified-diff authorization now uses Git's own apply inspection rather than scraping +++ b/ headers.
• The Sessions tab now uses blue for open logical tasks, amber for incomplete sessions where completion was not reported, green for completed sessions, and red only for actual errors.

Bump root/electron/status UI/lockfiles to 0.21.9.