chore: simplify commitlint flow

.github/actions/base/commit-check/action.yml

@@ -62,32 +62,15 @@ runs:
           bun i --frozen-lockfile
         fi
 
-    - name: Install commitlint globally if no config
-      if: github.event_name == 'pull_request' && steps.commitlint-config.outputs.has-config == 'false'
-      shell: bash
-      working-directory: ${{ env.HOLDEX_WORKING_DIR || '.' }}
-      run: |
-        if [ "${{ inputs.package-manager }}" = "pnpm" ]; then
-          pnpm add -D @commitlint/config-conventional
-        elif [ "${{ inputs.package-manager }}" = "npm" ]; then
-          npm install --save-dev @commitlint/config-conventional
-        else
-          bun i -D @commitlint/config-conventional
-        fi
-
-    - name: Create commitlint config if missing
-      if: github.event_name == 'pull_request' && steps.commitlint-config.outputs.has-config == 'false'
-      shell: bash
-      working-directory: ${{ env.HOLDEX_WORKING_DIR || '.' }}
-      run: |
-        echo "extends:" > .commitlintrc.yml
-        echo "  - '@commitlint/config-conventional'" >> .commitlintrc.yml
-
     - name: Check PR title
       if: github.event_name == 'pull_request'
       shell: bash
       working-directory: ${{ env.HOLDEX_WORKING_DIR || '.' }}
       env:
         PR_TITLE: ${{ github.event.pull_request.title }}
       run: |
-        echo "$PR_TITLE" | commitlint
+        if [ "${{ steps.commitlint-config.outputs.has-config }}" = "true" ]; then
+          echo "$PR_TITLE" | commitlint
+        else
+          echo "$PR_TITLE" | commitlint --default-config
+        fi

ACTIONS.md

@@ -25,9 +25,9 @@
 - Intended as the first step before calling local-path actions from that checkout.
 
 > [!WARNING]
 > Keep `base/checkout` backward compatible. Workflows reference the action as `.../base/checkout@main`, so any breaking change merged to this repo’s `main` will immediately break consumers.
 >
 > This also applies to the `ref` input: existing workflows often pass `ref: main` (a branch name) for the _target_ repo checkout, so don’t change `ref` semantics in a way that would require a commit SHA.
 
 ### `base/setup-runtime`
 
@@ -42,7 +42,7 @@
 - Validates allowed `package-manager` values.
 - For `bun`: installs Bun runtime.
 - For `pnpm`/`npm`: installs Node.js.
 - For `pnpm`: installs pnpm using `package.json#packageManager` when present, otherwise falls back to `latest`.
 - Respects `HOLDEX_WORKING_DIR` env var for `package.json` detection when set.
 
 ### `base/prettier`
@@ -80,7 +80,7 @@
 - Filters/uses markdown-only changed files.
 - Skips execution if no markdown files changed.
 - Installs `rumdl` globally using selected package manager.
 - Runs `rumdl check --output-format github --fail-on error` on changed markdown files.
 - Respects `HOLDEX_WORKING_DIR` env var: all steps run in that directory when set.
 
 ### `base/commit-check`
@@ -98,7 +98,7 @@
 - Detects commitlint configuration from standard config files or `package.json`.
 - If config exists, installs dependencies in repo context:
   - `bun i --frozen-lockfile`, `pnpm install --frozen-lockfile`, or `npm ci`.
-- If config does not exist, installs `@commitlint/config-conventional` and creates fallback `.commitlintrc.yml`.
+- If config does not exist, validates using `commitlint --default-config`.
 - Validates PR title via `commitlint`.
 - Respects `HOLDEX_WORKING_DIR` env var: all steps run in that directory when set.