refactor: replace inline HERMES_HOME re-implementations with get_hermes_home()

16 callsites across 14 files were re-deriving the hermes home path
via os.environ.get('HERMES_HOME', ...) instead of using the canonical
get_hermes_home() from hermes_constants. This breaks profiles — each
profile has its own HERMES_HOME, and the inline fallback defaults to
~/.hermes regardless.

Fixed by importing and calling get_hermes_home() at each site. For
files already inside the hermes process (agent/, hermes_cli/, tools/,
gateway/, plugins/), this is always safe. Files that run outside the
process context (mcp_serve.py, mcp_oauth.py) already had correct
try/except ImportError fallbacks and were left alone.

Skipped: hermes_constants.py (IS the implementation), env_loader.py
(bootstrap), profiles.py (intentionally manipulates the env var),
standalone scripts (optional-skills/, skills/), and tests.

gateway/builtin_hooks/boot_md.py

@@ -24,7 +24,8 @@ from pathlib import Path
 
 logger = logging.getLogger("hooks.boot-md")
 
-HERMES_HOME = Path(os.environ.get("HERMES_HOME", Path.home() / ".hermes"))
+from hermes_constants import get_hermes_home
+HERMES_HOME = get_hermes_home()
 BOOT_FILE = HERMES_HOME / "BOOT.md"
 
 

gateway/platforms/webhook.py

@@ -203,10 +203,8 @@ class WebhookAdapter(BasePlatformAdapter):
 
     def _reload_dynamic_routes(self) -> None:
         """Reload agent-created subscriptions from disk if the file changed."""
-        from pathlib import Path as _Path
-        hermes_home = _Path(
-            os.getenv("HERMES_HOME", str(_Path.home() / ".hermes"))
-        ).expanduser()
+        from hermes_constants import get_hermes_home
+        hermes_home = get_hermes_home()
         subs_path = hermes_home / _DYNAMIC_ROUTES_FILENAME
         if not subs_path.exists():
             if self._dynamic_routes: