Establish GitHub Actions CI Pipeline

This change introduces a new GitHub Actions workflow to establish a Continuous Integration (CI) pipeline. The pipeline is configured to run on pushes and pull requests to the `main` branch, and it includes steps for dependency caching, linting, type checking, format verification, and security auditing. This will help to ensure code quality, type safety, and security for the project.

Fixes #2711

---
*PR created automatically by Jules for task [1531126202162558856](https://jules.google.com/task/1531126202162558856) started by @arii*

Author: github-actions[bot]

.github/workflows/ci.yml

@@ -0,0 +1,71 @@
+name: HRM Dashboard - CI
+
+on:
+  push:
+    branches:
+      - leader
+  pull_request:
+    branches:
+      - leader
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  ci:
+    runs-on: ubuntu-latest
+    permissions:
+      pull-requests: write
+    steps:
+      - name: Checkout code
+        uses: actions/checkout@v4
+        with:
+          fetch-depth: 0
+
+      - name: Setup pnpm
+        uses: pnpm/action-setup@v4
+        with:
+          version: 8
+
+      - name: Setup Node.js
+        uses: actions/setup-node@v4
+        with:
+          node-version: '20'
+          cache: 'pnpm'
+
+      - name: Install dependencies
+        run: pnpm install --frozen-lockfile
+
+      - name: Lint
+        run: pnpm run lint
+
+      - name: Type check
+        run: pnpm exec tsc --noEmit
+
+      - name: Knip
+        run: pnpm run knip
+
+      - name: Format check
+        run: pnpm run format:check
+
+      - name: Security audit
+        run: pnpm audit --prod --audit-level=high
+
+      - name: Validate PR commits
+        if: github.event_name == 'pull_request'
+        id: lint
+        run: npx commitlint --from ${{ github.event.pull_request.base.sha }} --to ${{ github.event.pull_request.head.sha }} --verbose
+
+      - name: Post Comment on Failure
+        if: failure() && steps.lint.conclusion == 'failure'
+        uses: peter-evans/create-or-update-comment@v4
+        with:
+          issue-number: ${{ github.event.pull_request.number }}
+          body: |
+            :no_entry: **Commit Message Linting Failed**
+
+            One or more of your commit messages do not follow the project's conventions.
+            Please review the [commitlint logs](${{ github.server_url }}/${{ github.repository }}/actions/runs/${{ github.run_id }}) for more details.
+
+            You can also refer to the [commit message guidelines](https://github.com/conventional-changelog/commitlint/#what-is-commitlint) for help.