- promote major sections to consistent heading levels
- replace self-distribution notes with step-by-step release guide

- rewrite README and add CONTRIBUTING guide for the new workflow
- delete devcontainer setup and AGENTS notes no longer needed
- point the Margin generator ID at the new GitHub repository

- push workflow now targets git@tangled.sh:anton.galiglobal.com/frontpage_firefox_plugin

- Rewrite README with Margin/Frontpage workflows, mirrors, and setup notes
- Update manifest metadata, homepage link, and bump version to 0.1.6

- add margin submit API, content script, and popup tab experience
- rename extension to ATProto Social and bump version to 0.1.5

Added Tangled note to README.md