perf: round 10 — auth alloc purge, parent-herd batching, query-shape pack, NC 304s

Benchmark-gated (benches/ROUND10.md; every change carries a BEFORE/AFTER
harness with equivalence/safety gates — two designs were rejected or
rewritten by their own benches before adoption):

- Auth hot path: TokenClaims/CurrentUser display fields to Arc<str>, role
  to inline SmolStr end-to-end (Bearer, cookie, Basic-auth cache) — 4→1
  allocs per authenticated request, 3→0 per warm DAV request; JWT
  Encoding/Decoding/Validation built once.
- Cold shared-album herd: leader-inline parent batching in PgAclEngine
  (+ cascade try_get_with single-flight) — 100→2 parent queries per
  100-thumb cold herd, herd wall 1.9x, sequential + warm paths unchanged,
  all ROUND8/9 safety gates plus new herd-equivalence gates.
- Query-shape pack: share download double-fetch 2→1 (2.18x), contact-group
  COUNT(*) 14.9x, save_faces UNNEST 3.9x, playlist reorder UNNEST 63.7x
  (now atomic), search files∥folders join! 1.45x, move drive-lookup join!
  2.14x, trash partial (drive_id, trashed_at) indexes, CalDAV event-gate
  narrow read, favorites/recents binary-decode port, dead count_files
  removed.
- NC surface: preview + avatar honour If-None-Match (e2e: 5 KB and 197 KB
  → 0 bytes per revalidation), avatar WebP→PNG transcode memoised,
  PROPFIND/trashbin integer+date emits on stack formatters, folder-header
  enrichment join!, chunk-PUT retry stat folded into create_new open.
- common::fmt integer rendering rewritten on the std 2-digit LUT after the
  round's own bench caught the div-loop losing to to_string (16.1 ns vs
  22.5; speeds every prior-round call site).
- Micro-pack: WebDAV scope probe borrow-only, ShareService base_url
  snapshot, cookie_secure OnceLock, Arc'd AES-GCM cipher, stack request-id,
  tantivy analyzer clone dropped.
- SPA: search stale-guard + AbortController (10→1 completed round-trips,
  stale-clobber gone), getFolder in-flight dedup, gridColumns matchMedia
  hoist (10k→0 style reads).

Backend: cargo fmt + clippy -D warnings clean, 524 tests green.
Frontend: npm run check clean, 301 vitest green.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_018DdM7V7M3QPW7HEHg3gLov

src/infrastructure/services/search_index/tantivy_content_index.rs

@@ -238,8 +238,10 @@ impl TantivyContentIndex {
     }
 
     /// Tokenize `raw` with the index analyzer (simple split + lowercase).
-    fn query_tokens(analyzer: &TextAnalyzer, raw: &str) -> Vec<String> {
-        let mut analyzer = analyzer.clone();
+    /// Takes the analyzer by value — the caller's per-search clone is the
+    /// only one needed; cloning the boxed tokenizer chain again here doubled
+    /// the per-query allocation for nothing.
+    fn query_tokens(mut analyzer: TextAnalyzer, raw: &str) -> Vec<String> {
         let mut tokens = Vec::new();
         let mut stream = analyzer.token_stream(raw);
         while stream.advance() && tokens.len() < MAX_QUERY_TOKENS {
@@ -337,7 +339,7 @@ impl TantivyContentIndex {
         raw_query: &str,
         limit: usize,
     ) -> Result<Vec<ContentHitDto>, DomainError> {
-        let tokens = Self::query_tokens(&analyzer, raw_query);
+        let tokens = Self::query_tokens(analyzer, raw_query);
         if tokens.is_empty() {
             return Ok(Vec::new());
         }