perf: round 11 finale — benchmark verdicts, geo min(uuid) rollback, ROUND11.md

- benches/ROUND11.md: final BEFORE/AFTER numbers for all 21 micro
  sections, the 5 query sections, the 4 log-writer arms, the SPA gates,
  and the two cross-round regression guards (bench_row_path 2.52x,
  bench_dto_map — both byte-identical)
- ROLLBACK (gate-caught): min(fm.file_id)::text geo-cluster cast —
  PostgreSQL has no min(uuid) aggregate; the bench section now reproduces
  the rejection and the per-row-cast original stays
- REJECTED (bench-measured): tracing-appender non-blocking writer —
  slower than sync on fast sinks (1.41M vs 0.99M ev/s, worse tail) and
  the slow-sink drain gate showed shutdown tail-loss risk for the audit
  channel; dep moved to dev-dependencies (harness only)
- RateLimiter final form: lock-free get + insert (8.0 → 6.0 allocs, wall
  neutral; and_upsert_with variant rejected at 2 365 ns)
- fix: TrashedItemParts insertion had stolen TrashedItem's derive line
  (caught by clippy --all-targets)
- grant_role enum values corrected in the queries bench

Validation: cargo fmt + clippy --all-features --all-targets -D warnings
clean; cargo test --workspace 524 passed / 0 failed; frontend npm run
check 0 errors + vitest 306 passed (1 pre-existing round-7 wall-clock
gate flaked only under concurrent Rust-build CPU contention; passes in
isolation)

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01ABhTEHuGujvwoodh67Kga7

src/infrastructure/repositories/pg/file_blob_read_repository.rs

@@ -625,10 +625,12 @@ impl FileBlobReadRepository {
             SELECT count(*)              AS n,
                    avg(fm.longitude)     AS clng,
                    avg(fm.latitude)      AS clat,
-                   -- Cast once per cluster, not once per row: uuid byte
-                   -- order == canonical-text order, so the chosen sample
-                   -- is identical (benches/ROUND11.md §Q4).
-                   min(fm.file_id)::text AS sample_id
+                   -- NOTE: `min(fm.file_id)::text` (cast per cluster, not
+                   -- per row) was attempted in ROUND11 §Q4 and REJECTED by
+                   -- its benchmark gate: PostgreSQL has no `min(uuid)`
+                   -- aggregate, and adding a custom one is schema surface
+                   -- this viewport query doesn't justify.
+                   min(fm.file_id::text) AS sample_id
               FROM storage.file_metadata fm
               JOIN storage.files fi ON fi.id = fm.file_id
              WHERE fi.drive_id IN (