ci: add branch input to Format Code workflow (#326)

Enables manual triggering of the Format Code workflow against any branch
via `workflow_dispatch` input.

## Changes

- **Added `branch` input**: Optional parameter in `workflow_dispatch`
trigger that accepts branch names
- **Updated checkout**: Uses `inputs.branch` when provided, falls back
to `github.ref` otherwise
- **Fixed branch detection**: Modified default branch check, format
commits step, and force push step to use the actual target branch (from
input or context)

## Behavior

```yaml
# Manual trigger via GitHub UI or API
inputs:
  branch: 'feature/my-branch'  # Optional - omit to use current branch
```

When `branch` is specified:
- Checks out the specified branch
- Validates it's not the default branch
- Formats all commits on that branch
- Force-pushes formatted commits back to the same branch

When omitted, maintains existing behavior using the triggered branch
context.

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<details>

<summary>Original prompt</summary>

> 
> ----
> 
> *This section details on the original issue you should resolve*
> 
> <issue_title>Support passing a branch to the Format Code
workflow</issue_title>
> <issue_description>Add a branch input to the Format Code
`workflow_dispatch` workflow.</issue_description>
> 
> ## Comments on the Issue (you are @copilot in this section)
> 
> <comments>
> </comments>
> 


</details>

- Fixes #325

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Author: LayZeeDK

.github/workflows/format.yml

@@ -2,6 +2,11 @@ name: Format Code
 
 on:
   workflow_dispatch:
+    inputs:
+      branch:
+        description: 'Branch to format (defaults to current branch if not specified)'
+        required: false
+        type: string
 
 permissions:
   contents: write # needed to amend commits and force push
@@ -17,6 +22,8 @@ jobs:
           fetch-depth: 0
           # Use token that allows force push
           token: ${{ secrets.GITHUB_TOKEN }}
+          # Use the branch input if provided, otherwise use the default branch
+          ref: ${{ inputs.branch || github.ref }}
 
       - name: Check if running on default branch
         id: check-branch
@@ -25,8 +32,17 @@ jobs:
           DEFAULT_BRANCH=$(gh repo view --json defaultBranchRef --jq '.defaultBranchRef.name')
           echo "default-branch=$DEFAULT_BRANCH" >> $GITHUB_OUTPUT
 
+          # Determine the branch being processed
+          # If a branch was specified via workflow input, use that
+          # Otherwise, use the branch from GITHUB_REF
+          if [ -n "${{ inputs.branch }}" ]; then
+            BRANCH="${{ inputs.branch }}"
+          else
+            BRANCH="${GITHUB_REF#refs/heads/}"
+          fi
+
           # Prevent running on the default branch
-          if [ "$GITHUB_REF" == "refs/heads/$DEFAULT_BRANCH" ]; then
+          if [ "$BRANCH" == "$DEFAULT_BRANCH" ]; then
             echo "Error: This workflow cannot run on the default branch ($DEFAULT_BRANCH)"
             exit 1
           fi
@@ -49,7 +65,13 @@ jobs:
           DEFAULT_BRANCH="${{ steps.check-branch.outputs.default-branch }}"
 
           # Get the current branch name
-          CURRENT_BRANCH="${GITHUB_REF#refs/heads/}"
+          # If a branch was specified via workflow input, use that
+          # Otherwise, use the branch from GITHUB_REF
+          if [ -n "${{ inputs.branch }}" ]; then
+            CURRENT_BRANCH="${{ inputs.branch }}"
+          else
+            CURRENT_BRANCH="${GITHUB_REF#refs/heads/}"
+          fi
 
           # Check if this branch has an open pull request and use its target branch
           BASE_BRANCH=$(gh pr view "$CURRENT_BRANCH" --json baseRefName --jq '.baseRefName' 2>/dev/null || echo "")
@@ -213,8 +235,17 @@ jobs:
 
       - name: Force push formatted commits
         run: |
+          # Determine the branch name to push to
+          # If a branch was specified via workflow input, use that
+          # Otherwise, use the branch from github.ref_name
+          if [ -n "${{ inputs.branch }}" ]; then
+            BRANCH_NAME="${{ inputs.branch }}"
+          else
+            BRANCH_NAME="${{ github.ref_name }}"
+          fi
+
           # Force push the reformatted branch
           # Use --force-with-lease for safety (protects against concurrent updates)
           # Note: --force-if-includes requires Git 2.30+, so we use just --force-with-lease
-          git push --force-with-lease origin "HEAD:${{ github.ref_name }}"
-          echo "✓ Successfully pushed formatted commits to ${{ github.ref_name }}"
+          git push --force-with-lease origin "HEAD:$BRANCH_NAME"
+          echo "✓ Successfully pushed formatted commits to $BRANCH_NAME"