docs: update version to v1.4.7 and organize documentation

- Update package.json version to v1.4.7
- Update README.md header to v1.4.7
- Update GEMINI.md version references to v1.4.7
- Update RECOVERY_PLAYBOOK.md version to v1.4.7
- Update SECURITY_AUDIT_REPORT.md version to v1.4.7
- Move documentation files to doc/ directory for better organization
- Add new documentation files: LOCAL_TESTING_GUIDE.md, SERVE.md, TAILS_OFFLINE_PLAYBOOK.md
- Add Makefile and serve.ts for improved development workflow

doc/SERVE.md

@@ -0,0 +1,44 @@
+# Serving the built `dist/` folder
+
+This project provides two lightweight ways to serve the static `dist/` folder locally (both are offline):
+
+1) Bun static server (uses `serve.ts`)
+
+```bash
+# From project root
+bun run serve
+# or
+bun ./serve.ts
+# Open: http://127.0.0.1:8000
+```
+
+1) Python HTTP server (zero-deps, portable)
+
+```bash
+# From the `dist` folder
+cd dist
+python3 -m http.server 8000
+# Open: http://localhost:8000
+```
+
+Convenience via `package.json` scripts:
+
+```bash
+# Run Bun server
+bun run serve
+
+# Run Python server (from project root)
+bun run serve:py
+```
+
+Makefile shortcuts:
+
+```bash
+make serve-bun   # runs Bun server
+make serve-local # runs Python http.server
+```
+
+Notes:
+
+- The Bun server sets correct `Content-Type` for `.wasm` and other assets.
+- Always use HTTP (localhost) rather than opening `file://` to avoid CORS/file restrictions.