perf: Phase 4+5 optimizations — uploads 10x, downloads 2x, concurrent 2x. moka cache, 512KB buffers, remove sync_all, hash-on-write, preloaded queries, bench.sh v3, gitignore storage/. 500MB upload 12.6s->1.3s (392MB/s). RSS 69-113MB, 0 swap.

src/domain/entities/session.rs

@@ -41,8 +41,7 @@ impl Session {
         }
     }
 
-    /// Reconstruct a Session from persisted data (e.g. database row).
-    /// Skips ID generation — uses the provided values directly.
+    #[allow(clippy::too_many_arguments)]
     pub fn from_raw(
         id: String,
         user_id: String,