feat: add get_partial_user method to StackServerApp and AsyncStackServerApp

- Decode JWT access token claims locally without network request
- Return TokenPartialUser with user ID, display name, email, and flags
- Return None when no token store or no access token available
- Support token_store override parameter for per-call flexibility
- Method is synchronous on both classes since it performs no I/O

sdks/implementations/python/src/stack_auth/_app.py

@@ -12,6 +12,7 @@ from __future__ import annotations
 
 from typing import Any, Optional
 
+from stack_auth._auth import TokenPartialUser, decode_access_token_claims
 from stack_auth._client import AsyncAPIClient, SyncAPIClient
 from stack_auth._constants import DEFAULT_BASE_URL
 from stack_auth._pagination import PaginatedResult, _PaginationMeta
@@ -154,6 +155,43 @@ class StackServerApp:
     def __exit__(self, *_: Any) -> None:
         self.close()
 
+    # -- partial user (local JWT decode) -------------------------------------
+
+    def get_partial_user(
+        self,
+        *,
+        token_store: TokenStoreInit | None = _UNSET,
+    ) -> TokenPartialUser | None:
+        """Get minimal user info from the access token without a network request.
+
+        Decodes the JWT payload from the token store's access token to extract
+        partial user information. Does NOT verify the token's signature.
+
+        Args:
+            token_store: Override token storage for this call. If not provided,
+                uses the instance's token store. Pass ``None`` explicitly to
+                indicate no token store.
+
+        Returns:
+            A :class:`TokenPartialUser` with user ID and claims from the JWT,
+            or ``None`` if no access token is available or the token is malformed.
+        """
+        if token_store is _UNSET:
+            store = self._token_store
+        elif token_store is None:
+            store = None
+        else:
+            store = resolve_token_store(token_store, self._project_id)
+
+        if store is None:
+            return None
+
+        access_token = store.get_stored_access_token()
+        if access_token is None:
+            return None
+
+        return decode_access_token_claims(access_token)
+
     # -- user CRUD -----------------------------------------------------------
 
     def get_user(self, user_id: str) -> ServerUser | None:
@@ -1433,6 +1471,46 @@ class AsyncStackServerApp:
     async def __aexit__(self, *_: Any) -> None:
         await self.aclose()
 
+    # -- partial user (local JWT decode) -------------------------------------
+
+    def get_partial_user(
+        self,
+        *,
+        token_store: TokenStoreInit | None = _UNSET,
+    ) -> TokenPartialUser | None:
+        """Get minimal user info from the access token without a network request.
+
+        Decodes the JWT payload from the token store's access token to extract
+        partial user information. Does NOT verify the token's signature.
+
+        Note: This method is synchronous because it performs no network I/O.
+        It only decodes the JWT payload locally.
+
+        Args:
+            token_store: Override token storage for this call. If not provided,
+                uses the instance's token store. Pass ``None`` explicitly to
+                indicate no token store.
+
+        Returns:
+            A :class:`TokenPartialUser` with user ID and claims from the JWT,
+            or ``None`` if no access token is available or the token is malformed.
+        """
+        if token_store is _UNSET:
+            store = self._token_store
+        elif token_store is None:
+            store = None
+        else:
+            store = resolve_token_store(token_store, self._project_id)
+
+        if store is None:
+            return None
+
+        access_token = store.get_stored_access_token()
+        if access_token is None:
+            return None
+
+        return decode_access_token_claims(access_token)
+
     # -- user CRUD -----------------------------------------------------------
 
     async def get_user(self, user_id: str) -> ServerUser | None: