docs(config): add deploy command, update README and CLAUDE.md

Adds bun run deploy script, deployment docs to README, and updates
CLAUDE.md with deployment info, current patterns, and rule to keep
docs in sync with changes.

README.md

@@ -15,6 +15,16 @@ bun run build     # Static build to dist/
 bun run preview   # Preview production build
 ```
 
+## Deployment
+
+Deploys to Cloudflare Pages via Gitea Actions on push to `main`. To deploy manually:
+
+```sh
+bun run deploy    # Build + deploy to Cloudflare Pages
+```
+
+Requires `CLOUDFLARE_API_TOKEN` and `CLOUDFLARE_ACCOUNT_ID` (set as Gitea secrets for CI, or via `wrangler login` locally).
+
 ## Linting & Formatting
 
 ```sh