feat: per-attribute preservation flags -p/-t/-o/-g with --no-* negations (protocol 2.22.0)

Split FastSync's single use_metadata bundle into four independent rsync-parity attributes: preserve_perms, preserve_times, preserve_owner, preserve_group. use_metadata is now a derived transport bit (config_derived_use_metadata).

CLI: real -p/--perms, -t/--times, -o/--owner, -g/--group plus --no-perms/--no-times/--no-owner/--no-group (short and long) and --no-preserve; -a is now rsync -rlptgoD; --preserve = -pt; -A implies -p; -X does not; --chmod implies -p; --usermap/--groupmap/--chown imply owner/group per side; --incremental/--delta still auto-preserve unless negated.

Receiver: per-attribute FileAttrPolicy gating for files, dirs (modes applied at end of transfer), symlinks and specials; rsync -E read-bit rule; new files get source_mode & ~umask sanitized (no group/other write); per-side identity resolution; deferred directory metadata; batch dir-metadata replay; daemon modules without 'client owner = yes' no longer refuse plain -a but force super off (no ownership) with a warning.

Wire: PROTOCOL_VERSION 2.21.0 -> 2.22.0 (four appended config bools, golden 653 / 95530566005420798). FileMetadata/chunk/batch framing unchanged. Docs/CHANGELOG/CMake updated to 2.22.0.

HANDOFF.md

@@ -8,8 +8,8 @@
 - **Release PR #284 (`dev` -> `main`)** open, CI green (run 553).
   `main` is protected: it needs review/approval to merge.
   https://gitea.tap-tap.win/TapTap/FastSync/pulls/284
-- **`PROTOCOL_VERSION` = `"2.21.0"`** (`src/shared/config.h`); CMake
-  `project(FastFileTransfer VERSION 2.21.0)`.
+- **`PROTOCOL_VERSION` = `"2.22.0"`** (`src/shared/config.h`); CMake
+  `project(FastFileTransfer VERSION 2.22.0)`.
 - Working tree clean; no wave worktrees remain.
 
 ## What landed this session
@@ -37,6 +37,7 @@
 4. **Tooling:** benchmark accuracy (data mix, verification, percentiles, `tc`,
    `build-bench/`, `--warm` mode); `shell.nix` full toolchain and no build-on-entry;
    docs state push-only / remote-source unsupported.
+5. **Preserve-attribute split (protocol 2.22.0)** landed on `feat/preserve-attr-split`: per-attribute `-p/-t/-o/-g` + `--no-*` negations, `-a` = `-rlptgoD`, and the 2.21.0 → 2.22.0 wire bump.
 
 ## Next steps
 1. **Merge PR #284** (`dev` -> `main`) once reviewed (protected branch).