feat: enforce changelog entry via CI check

.github/workflows/ci_changelog_check.yaml

@@ -0,0 +1,59 @@
+name: ci_changelog_check
+
+# Runs on every PR event that could change which files are included.
+# 'labeled'/'unlabeled' are needed so that adding/removing the
+# 'no-changelog' label immediately re-evaluates the check.
+on:
+  pull_request:
+    branches:
+      - main
+    types:
+      - opened
+      - reopened
+      - synchronize
+      - labeled
+      - unlabeled
+
+permissions:
+  contents: read
+  pull-requests: read
+
+jobs:
+  changelog_check:
+    runs-on: ubuntu-latest
+    name: Check Changelog Entry
+
+    # Skip the whole job (shows as "skipped" = passing) when a maintainer
+    # has deliberately labelled the PR 'no-changelog'.
+    # Typical use-cases: CI-only fixes, typo corrections, dependency bumps.
+    if: "!contains(github.event.pull_request.labels.*.name, 'no-changelog')"
+
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@v4
+        with:
+          # Full history is required so tj-actions/changed-files can compare
+          # the PR branch against the base branch correctly.
+          fetch-depth: 0
+
+      - name: Detect changed files
+        id: changed_files
+        uses: tj-actions/changed-files@v44
+        with:
+          # Only care about the top-level CHANGELOG.md.
+          files: CHANGELOG.md
+
+      - name: Fail — no changelog entry found
+        if: steps.changed_files.outputs.any_changed == 'false'
+        run: |
+          echo "::error file=CHANGELOG.md::Missing changelog entry. Please add one before merging."
+          echo ""
+          echo "Every user-facing pull request must include an update to CHANGELOG.md."
+          echo "If this PR genuinely does not need a changelog entry (e.g. a CI fix,"
+          echo "a typo correction, or a dependency bump), ask a maintainer to add the"
+          echo "'no-changelog' label to skip this check."
+          exit 1
+
+      - name: Pass — changelog entry found
+        if: steps.changed_files.outputs.any_changed == 'true'
+        run: echo "CHANGELOG.md was updated. Check passed."

CHANGELOG.md

@@ -11,3 +11,7 @@ Scribe-Android tries to follow [semantic versioning](https://semver.org/), a MAJ
 Emojis for the following are chosen based on [gitmoji](https://gitmoji.dev/).
 
 # Scribe-Android 1.0.0
+
+### CI/CD
+
+- Added `ci_changelog_check` workflow to enforce `CHANGELOG.md` updates on all PRs targeting `main`, with support for a `no-changelog` label to skip the check when appropriate