fix(tools): profile-scoped checkpoint/snapshot paths, tool caches, TZ and schema paths under multiplex

Under `gateway.multiplex_profiles` one gateway process serves every profile
under ~/.hermes/profiles/NAME/; each routed turn runs with a context-local
HERMES_HOME override while `os.environ` still holds the DEFAULT profile's
values. Anything evaluated once at import, or memoised in a single unkeyed
module slot, therefore freezes the LAUNCH profile's value and leaks it into
every other profile's turns. This lands the tools-side half of that class:

- tools/process_registry.py, tools/environments/{modal,singularity}.py:
  `_checkpoint_path()` / `_snapshot_store()` resolve `get_hermes_home()` at
  call time (same seam as `tools/skills_tool._skills_dir`, so the existing
  `monkeypatch.setattr(CHECKPOINT_PATH)` test sites keep working). Completes
  the checkpoint_manager / sticker_cache half cherry-picked from #56315.
- plugins/platforms/feishu/feishu_comment_rules.py: `_MtimeCache` is now
  path-keyed (accepts a Path or a zero-arg resolver, one (mtime, data) slot
  per resolved path) with `invalidate()`; `_rules_file()` / `_pairing_file()`
  resolve the routed profile's files. Proposed in #63962.
- tools/tool_output_limits.py, tools/browser_tool.py, tools/browser_camofox.py:
  the process-lifetime config caches are dicts keyed by `hermes_home_key()`;
  the `_X_resolved` flags and the lifecycle reset keep their shape.
  tools/file_tools.py drops its private `file_read_max_chars` memo and reads
  the already mtime+path-cached `load_config_readonly()`.
- hermes_time.py: `get_timezone_name()`; when `is_multiplex_active()` the
  env `HERMES_TIMEZONE` (bridged from the default profile's config at gateway
  startup) is ignored in favour of the routed profile's config.yaml. Both
  sandbox TZ sites (code_execution_env/_tool) now use it.
- tools/cronjob_tools.py, tools/tts_tool.py, tools/skill_manager_tool.py:
  the static schema text is profile-neutral and `dynamic_schema_overrides=`
  rebuilds the `display_hermes_home()` / create-dir hint per
  `get_definitions()`, so a routed profile's model sees its own paths.

Refs #95685.

Co-authored-by: Nathan Shan <nathanielcrush51@gmail.com>
(cherry picked from commit 6d3fc6b07b3155c6196b1fd61a829283f1d7855c)

tools/process_registry.py

@@ -39,6 +39,15 @@ logger = logging.getLogger(__name__)
 
 # Crash-recovery checkpoint (gateway only)
 CHECKPOINT_PATH = get_hermes_home() / "processes.json"
+_CHECKPOINT_PATH_AT_IMPORT = CHECKPOINT_PATH
+
+
+def _checkpoint_path() -> Path:
+    """Active profile's checkpoint file at call time: the patched ``CHECKPOINT_PATH`` when a test
+    changed it, else live profile-scoped HERMES_HOME — the multiplexed gateway serves every
+    profile from one process, so the import-time constant would pin every profile's process
+    checkpoint to the launch home."""
+    return CHECKPOINT_PATH if CHECKPOINT_PATH != _CHECKPOINT_PATH_AT_IMPORT else get_hermes_home() / "processes.json"
 
 MAX_OUTPUT_CHARS = 200_000      # rolling output buffer
 FINISHED_TTL_SECONDS = 1800     # keep finished processes 30 minutes