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

Cargo.toml

@@ -20,10 +20,6 @@ tower-http = { version = "0.6.11", features = ["fs", "compression-gzip", "compre
 flate2 = "1.1.9"
 tracing = "0.1.44"
 tracing-subscriber = { version = "0.3.23", features = ["env-filter"] }
-# Round-11: moves log formatting+write off the async workers. `lossy(false)`
-# so audit lines are never dropped (emitters block only when the 128k-line
-# channel is full — backpressure, not loss). See benches/ROUND11.md.
-tracing-appender = "0.2"
 chrono = { version = "0.4.45", features = ["serde"] }
 # RFC 5545 iCalendar parser + emitter.
 #
@@ -146,6 +142,10 @@ bench = []
 
 [dev-dependencies]
 criterion = "0.5"
+# Round-11 L1 harness only (bench_log_writer): the non-blocking writer was
+# REJECTED for production — slower than sync on fast sinks and can lose
+# buffered tail lines at shutdown on slow ones (benches/ROUND11.md).
+tracing-appender = "0.2"
 
 [lints.rust]
 unexpected_cfgs = { level = "warn", check-cfg = ['cfg(integration_tests)'] }