refactor(filemeta): own RestoreStatus and drop the s3s dependency (A3c) (#7782)

Replace s3s::dto::{RestoreStatus, Timestamp} in filemeta with a
filemeta-owned RestoreStatus (same field names, OffsetDateTime expiry).
RestoreStatusOps and parse_restore_obj_status keep their signatures and
persisted rendering; the ecstore restore finalize / lifecycle restore
writers and rustfs RestoreObject now build the filemeta type.

- crates/filemeta: drop s3s; tokio "time" becomes a dev-dependency
  (the metacache tests got it through s3s feature unification).
- metadata_keys: drop the s3s half of the historical-source cross-check;
  PINNED, the pre-A3a fixture and per-character mutation still pin keys.
- new test re-renders the pre-A3a fixture restore value byte-for-byte.
- s3s footprint baselines 210 -> 209 files, ecstore 37 -> 36.

Refs rustfs/backlog#1735

scripts/check_s3s_footprint.sh

@@ -61,14 +61,14 @@ cd "$(dirname "$0")/.."
 # 213 -> 212 on 2026-09-14: rustfs/backlog#1735 A4 moved rio's trailer
 # handle behind rustfs_rio::TrailerSource; the only adapter imports s3s through
 # the app storage_api shim, so crates/rio no longer references s3s.
-S3S_IMPORT_FILES_BASELINE=210
+S3S_IMPORT_FILES_BASELINE=209
 S3_ERROR_LINES_BASELINE=1588
 # ecstore-scoped ratchet (rustfs/backlog#1842): the storage engine must not
 # know S3 wire/DTO types (ARCHITECTURE.md invariant 4). The S3-*consuming*
 # client was extracted to crates/s3-client, where s3s usage is legitimate;
 # this counter ratchets the remaining serving-side s3s references out of
 # crates/ecstore. Baseline verified on 2026-08-26.
-S3S_ECSTORE_FILES_BASELINE=37
+S3S_ECSTORE_FILES_BASELINE=36
 S3S_PATH_PATTERN='(^|[^"[:alnum:]_])s3s::'
 E2E_TEST_GLOB='--glob=!crates/e2e_test/**'