chore: add CodeQL workflow, PR template, and Dependabot config

.github/dependabot.yml

@@ -0,0 +1,24 @@
+version: 2
+updates:
+  - package-ecosystem: npm
+    directory: /
+    schedule:
+      interval: weekly
+      day: monday
+    open-pull-requests-limit: 10
+    labels:
+      - dependencies
+    commit-message:
+      prefix: "chore(deps):"
+
+  - package-ecosystem: github-actions
+    directory: /
+    schedule:
+      interval: weekly
+      day: monday
+    open-pull-requests-limit: 5
+    labels:
+      - dependencies
+      - ci
+    commit-message:
+      prefix: "ci(deps):"

.github/pull_request_template.md

@@ -0,0 +1,17 @@
+## Summary
+
+Brief description of the changes.
+
+## Changes
+
+- 
+
+## Testing
+
+- [ ] `bun run build` passes
+- [ ] `bun test` passes
+- [ ] Manual testing done (if applicable)
+
+## Notes
+
+Any additional context or trade-offs worth mentioning.

.github/workflows/codeql.yml

@@ -0,0 +1,30 @@
+name: CodeQL
+
+on:
+  pull_request:
+  push:
+    branches:
+      - main
+  schedule:
+    - cron: '0 6 * * 1'
+
+jobs:
+  analyze:
+    name: Analyze TypeScript
+    runs-on: ubuntu-latest
+
+    permissions:
+      security-events: write
+      contents: read
+
+    steps:
+      - name: Checkout
+        uses: actions/checkout@v4
+
+      - name: Initialize CodeQL
+        uses: github/codeql-action/init@v3
+        with:
+          languages: javascript-typescript
+
+      - name: Perform CodeQL Analysis
+        uses: github/codeql-action/analyze@v3

AGENTS.md

@@ -42,6 +42,21 @@ If tests fail, identify whether failures are pre-existing vs introduced by your
 - Use the **Nuclear Cleanup** sequence before and after manual testing to avoid leftover tmux sessions, worktrees, branches, and state files.
 - Follow plan safety rules exactly: `tmc-` test naming, no remote push flows during testing (`mc_pr` is structural only), and explicit SHA-based resets.
 
+## CI & GitHub Workflows
+
+- **CI** (`.github/workflows/ci.yml`) — Runs `bun run build` and `bun test` on PRs and pushes to `main`.
+- **Conventional Commits** (`.github/workflows/conventional-commits.yml`) — Validates PR titles follow the convention.
+- **CodeQL** (`.github/workflows/codeql.yml`) — Static analysis for TypeScript; runs on PRs, pushes to `main`, and weekly.
+- **Publish** (`.github/workflows/publish.yml`) — semantic-release to npm on `main`.
+- **Dependabot** (`.github/dependabot.yml`) — Opens weekly PRs for npm and GitHub Actions dependency updates. These use `chore(deps):` and `ci(deps):` commit prefixes.
+
+## Branch & Merge Rules
+
+- Direct pushes to `main` are blocked; all changes go through PRs.
+- Merge commits are disabled — only **squash** and **rebase** merges are allowed.
+- PRs require 1 approving review, passing `build-and-test` and `conventional-commits` checks, and all conversations resolved.
+- A PR template (`.github/pull_request_template.md`) is provided — fill it out when opening PRs.
+
 ## Release Notes for Agents
 
 - npm package output is `dist/` only (`package.json -> files`).