auth: use get_default_hermes_root() for shared nous_auth.json path

Replace hardcoded ~/.hermes/shared/ references with
get_default_hermes_root() / 'shared' so the cross-profile Nous auth
store lands in the correct location on every platform:

- Linux/macOS: ~/.hermes/shared/
- native Windows: %LOCALAPPDATA%\hermes\shared- Docker / custom HERMES_HOME: <root>/shared/

Updates _nous_shared_auth_dir(), the pytest seat-belt in
_nous_shared_store_path(), and the auth_add_command comment to match.
Previously Windows installs wrote to ~/.hermes/shared/ even though the
rest of the CLI uses %LOCALAPPDATA%\hermes, so profiles couldn't see
each other's shared credential.

hermes_cli/auth.py

@@ -2827,9 +2827,12 @@ def _poll_for_token(
 # import instead of running the full device-code flow every time.
 #
 # File lives at ${HERMES_SHARED_AUTH_DIR}/nous_auth.json, defaulting to
-# ~/.hermes/shared/nous_auth.json. It is OUTSIDE any named profile's
+# ``<hermes-root>/shared/nous_auth.json`` where ``<hermes-root>`` is what
-# HERMES_HOME so named profiles (which typically live under
+# ``get_default_hermes_root()`` returns — ``~/.hermes`` on Linux/macOS,
-# ~/.hermes/profiles/<name>/) all see the same file.
+# ``%LOCALAPPDATA%\hermes`` on native Windows, or the Docker/custom root.
+# It is OUTSIDE any named profile's HERMES_HOME so named profiles (which
+# typically live under ``<hermes-root>/profiles/<name>/``) all see the
+# same file.
 #
 # Written on successful login and on every runtime refresh so the stored
 # refresh_token stays current even if one profile refreshes and rotates it.
@@ -2846,25 +2849,33 @@ def _nous_shared_auth_dir() -> Path:
 
     Honors ``HERMES_SHARED_AUTH_DIR`` so tests can redirect it to a tmp
     path without touching the real user's home. Defaults to
-    ``~/.hermes/shared/``.
+    ``<hermes-root>/shared/``, where ``<hermes-root>`` is what
+    :func:`hermes_constants.get_default_hermes_root` returns — so
+    Linux/macOS classic installs land at ``~/.hermes/shared/``, native
+    Windows installs at ``%LOCALAPPDATA%\\hermes\\shared\\``, and
+    Docker / custom ``HERMES_HOME`` deployments at
+    ``<HERMES_HOME>/shared/``. Sits outside any named profile so all
+    profiles under the same root share the store.
     """
     override = os.getenv("HERMES_SHARED_AUTH_DIR", "").strip()
     if override:
         return Path(override).expanduser()
-    return Path.home() / ".hermes" / "shared"
+    from hermes_constants import get_default_hermes_root
+    return get_default_hermes_root() / "shared"
 
 
 def _nous_shared_store_path() -> Path:
     path = _nous_shared_auth_dir() / NOUS_SHARED_STORE_FILENAME
     # Seat belt: if pytest is running and this resolves to a path under the
-    # real user's home, refuse rather than silently corrupt cross-profile
+    # real user's Hermes root, refuse rather than silently corrupt cross-profile
     # state. Tests must set HERMES_SHARED_AUTH_DIR to a tmp_path (conftest
     # does not do this automatically — mirror the _auth_file_path() guard
     # so forgetting to set it fails loudly instead of writing to the real
     # shared store).
     if os.environ.get("PYTEST_CURRENT_TEST"):
+        from hermes_constants import get_default_hermes_root
         real_home_shared = (
-            Path.home() / ".hermes" / "shared" / NOUS_SHARED_STORE_FILENAME
+            get_default_hermes_root() / "shared" / NOUS_SHARED_STORE_FILENAME
         ).resolve(strict=False)
         try:
             resolved = path.resolve(strict=False)

hermes_cli/auth_commands.py

@@ -246,7 +246,7 @@ def auth_add_command(args) -> None:
 
     if provider == "nous":
         # Codex-style auto-import: if a shared Nous credential lives at
-        # ~/.hermes/shared/nous_auth.json (written by any previous
+        # <hermes-root>/shared/nous_auth.json (written by any previous
         # successful login), offer to import it instead of running the
         # full device-code flow. This makes `hermes --profile <name>
         # auth add nous --type oauth` a one-tap operation for users who