fix: correct Python permission handler in skills and custom-agents guides

Same fix as the steering guide — use correct 2-arg signature and
PermissionRequestResult dataclass return type.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: patniko

docs/guides/custom-agents.md

@@ -65,6 +65,7 @@ const session = await client.createSession({
 
 ```python
 from copilot import CopilotClient
+from copilot.types import PermissionRequestResult
 
 client = CopilotClient()
 await client.start()
@@ -87,7 +88,7 @@ session = await client.create_session({
             "prompt": "You are a code editor. Make minimal, surgical changes to files as requested.",
         },
     ],
-    "on_permission_request": lambda req: {"kind": "approved"},
+    "on_permission_request": lambda req, inv: PermissionRequestResult(kind="approved"),
 })
 ```
 

docs/guides/skills.md

@@ -43,6 +43,7 @@ await session.sendAndWait({ prompt: "Review this code for security issues" });
 
 ```python
 from copilot import CopilotClient
+from copilot.types import PermissionRequestResult
 
 async def main():
     client = CopilotClient()
@@ -54,7 +55,7 @@ async def main():
             "./skills/code-review",
             "./skills/documentation",
         ],
-        "on_permission_request": lambda req: {"kind": "approved"},
+        "on_permission_request": lambda req, inv: PermissionRequestResult(kind="approved"),
     })
 
     # Copilot now has access to skills in those directories