Add id field to actor object for consistency with Datasette actor format (#77)

* Add id field to actor object for consistency with Datasette actor format

This change adds an "id" field to the actor object returned by the GitHub
authentication callback. The id field follows the format "github:{user_id}"
which is consistent with Datasette's actor format conventions and ensures
unique identification of authenticated users.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Author: xrendan

README.md

@@ -64,6 +64,7 @@ Visit `/-/actor` when signed in to see the shape of the authenticated actor. It
 ```json
 {
     "actor": {
+        "id": "github:9599",
         "display": "simonw",
         "gh_id": "9599",
         "gh_name": "Simon Willison",
@@ -106,7 +107,7 @@ Note that GitHub allows users to change their username, and it is possible for o
 ```json
 {
     "allow": {
-        "gh_id": "9599"
+        "id": "github:9599"
     }
 }
 ```

datasette_auth_github/views.py

@@ -76,6 +76,7 @@ async def github_auth_callback(datasette, request, scope, receive, send):
     except ValueError:
         return await response_error(datasette, "Could not load GitHub profile")
     actor = {
+        "id": "github:{}".format(profile["id"]),
         "display": profile["login"],
         "gh_id": str(profile["id"]),
         "gh_name": profile["name"],

tests/test_datasette_auth_github.py

@@ -154,6 +154,7 @@ async def test_github_auth_callback(ds, mocked_github_api):
     )
     actor = ds.unsign(response.cookies["ds_actor"], "actor")["a"]
     assert {
+        "id": "github:123",
         "display": "demouser",
         "gh_id": "123",
         "gh_name": "GitHub User",