Add CLAUDE.md with codebase overview

CLAUDE.md

@@ -0,0 +1,64 @@
+# CLAUDE.md
+
+## Project Overview
+
+Chrome File Directory is a static HTML page that replicates the Chromium browser's file/directory listing UI. It provides a customizable template for displaying files and folders in a familiar Chrome-style layout. Originally derived from Chromium source code (BSD-licensed), with additional modifications by @willtheorangeguy.
+
+## Repository Structure
+
+```
+├── index.html            # Main file directory page (simplified, customizable version)
+├── index_chromium.html   # Original Chromium file directory page (reference)
+├── style.css             # External stylesheet (references imgs/ for icons)
+├── icons/                # Icon assets (file.png, folder.png, up.png)
+├── docs/                 # Documentation site (usage, customization, legal)
+├── Dockerfile            # Nginx-based container for serving the page
+├── package.json          # npm metadata (no dependencies or real scripts)
+├── .github/
+│   ├── workflows/        # CI: GitHub Pages deploy, Docker build/push, GitLeaks
+│   ├── ISSUE_TEMPLATE/   # Bug report, feature request, question templates
+│   ├── agents/           # GitHub Copilot agent configs (docs, lint, test)
+│   └── dependabot.yml    # Automated dependency updates
+```
+
+## Key Files
+
+- **`index.html`** — The primary deliverable. A self-contained HTML page with inline CSS. Edit this to customize the directory listing. Icons reference `icons/` directory.
+- **`style.css`** — External stylesheet variant. Note: icon paths use `imgs/` (differs from `index.html` which uses `icons/`).
+- **`index_chromium.html`** — The original unmodified Chromium source. Keep as reference; do not modify.
+
+## Development
+
+**No build step or dependencies.** This is a pure static HTML/CSS project. Open `index.html` in a browser to preview.
+
+**Running locally with Docker:**
+
+```bash
+docker build -t chrome-file-directory .
+docker run -p 8080:80 chrome-file-directory
+```
+
+**No test suite exists.** The `npm test` script is a placeholder that exits with an error.
+
+## CI/CD Workflows
+
+- **Pages** (`pages.yml`): Deploys to GitHub Pages on push to `main`.
+- **Docker** (`docker-pubish.yml`): Builds and pushes to `ghcr.io` on push to `main`, tags, PRs, and daily schedule.
+- **GitLeaks** (`gitleaks.yml`): Scans for secrets on push, PR, and manual trigger.
+
+## Code Conventions
+
+- Dual copyright headers: Chromium BSD + @willtheorangeguy. Preserve both in modified files.
+- HTML uses 2-space indentation.
+- CSS uses 2-space indentation.
+- Prettier is configured as a transformer via DeepSource (`.deepsource.toml`).
+- Commit messages follow conventional commits style: `feat(scope):`, `fix(scope):`, `build(deps):`.
+
+## Licensing
+
+- BSD-2-Clause (primary, `LICENSE.md`)
+- Chromium BSD license (`LICENSE_chromium.md`) applies to original Chromium-derived code
+
+## Contributing
+
+Follow GitHub Flow: branch, commit, open PR. See `CONTRIBUTING.md` for full guidelines. Use provided issue templates for bugs, features, and questions.