fix: repair regenerate-models workflow stale add glob and branch clash

The `add:` pathspec `_*_generated.py` stopped matching anything after the
generated files were renamed (PR #765 dropped the `_generated` suffix),
so the workflow has been silently producing no commits since 2026-04-29.
After PR #792 swapped to `apify/actions/signed-commit`, the pre-existing
local `git switch -c "$BRANCH"` step also clashed with the action's
`create-branch: true` flow (its `git fetch ... $BRANCH:refs/heads/$BRANCH`
refuses to overwrite a checked-out branch), leaving dangling empty
branches like `update-models-docs-pr-2546` / `-2548`.

This fixes the `add:` list to the actual filenames and skips the local
branch creation when the remote branch doesn't yet exist, letting
signed-commit handle that path; existing branches are still pre-checked-out
locally and `create-branch` is set to `false` for that case.

Author: vdusek

.github/workflows/manual_regenerate_models.yaml

@@ -1,4 +1,4 @@
-# This workflow regenerates Pydantic models and TypedDicts (src/apify_client/_{models,typeddicts}_generated.py) from the OpenAPI spec.
+# This workflow regenerates Pydantic models, TypedDicts, and Literal aliases (src/apify_client/_{models,typeddicts,literals}.py) from the OpenAPI spec.
 #
 # It can be triggered in two ways:
 #   1. Automatically via workflow_dispatch from the apify-docs CI pipeline.
@@ -63,15 +63,20 @@ jobs:
         with:
           token: ${{ secrets.APIFY_SERVICE_ACCOUNT_GITHUB_TOKEN }}
 
-      # If the branch already exists on the remote (e.g. from a previous run, possibly with reviewer commits),
-      # check it out to build on top of it instead of starting fresh.
-      - name: Switch to existing branch or create a new one
+      # If the branch already exists on the remote (e.g. from a previous run, possibly with reviewer
+      # commits), check it out so regeneration builds on top of it. Otherwise stay on the default
+      # branch and let the signed-commit step below create the remote branch — its create-branch
+      # flow does `git fetch ... $BRANCH:refs/heads/$BRANCH` which fails if $BRANCH is already
+      # checked out locally.
+      - name: Set up branch
+        id: branch-setup
         run: |
           if git ls-remote --exit-code --heads origin "$BRANCH" > /dev/null 2>&1; then
-            git fetch origin "$BRANCH"
+            git fetch origin "$BRANCH":"$BRANCH"
             git switch "$BRANCH"
+            echo "create_branch=false" >> "$GITHUB_OUTPUT"
           else
-            git switch -c "$BRANCH"
+            echo "create_branch=true" >> "$GITHUB_OUTPUT"
           fi
 
       # Download the pre-built OpenAPI spec artifact from the apify-docs workflow run.
@@ -109,10 +114,10 @@ jobs:
         uses: apify/actions/signed-commit@v1.0.0
         with:
           message: ${{ env.TITLE }}
-          add: 'src/apify_client/_*_generated.py'
+          add: 'src/apify_client/_models.py src/apify_client/_typeddicts.py src/apify_client/_literals.py'
           github-token: ${{ secrets.APIFY_SERVICE_ACCOUNT_GITHUB_TOKEN }}
           branch: ${{ env.BRANCH }}
-          create-branch: 'true'
+          create-branch: ${{ steps.branch-setup.outputs.create_branch }}
 
       - name: Create or update PR
         if: steps.commit.outputs.committed == 'true'