chore(release): publish as real-browser-cli

- Rename the PyPI distribution from browser-cli to real-browser-cli after PyPI rejected the original name as too similar to an existing project.
- Keep the installed console command as browser-cli so user-facing CLI usage remains unchanged.
- Add README-based package metadata, author information, and project URLs so PyPI renders a proper project description.
- Centralize the PyPI distribution name for importlib.metadata version lookups used by the CLI, doctor command, and remote user agent.
- Document uv tool install, optional fast extra installation, and upgrade commands.
- Bump package and extension metadata to 0.14.3 for the republished release.

extension/manifest.json

@@ -1,7 +1,7 @@
 {
   "manifest_version": 3,
   "name": "browser-cli",
-  "version": "0.14.2",
+  "version": "0.14.3",
   "description": "Control your browser from the terminal or Python SDK",
   "permissions": [
     "tabs",