* docs(skills): add agent skill for Obscura
Adds skills/obscura/SKILL.md following the agent-skill convention used
by addyosmani/agent-skills and vercel-labs/agent-browser. AI coding
agents that scan a repo for SKILL.md files will discover Obscura and
know when to reach for it instead of Chrome.
Covers: build (with and without stealth), CLI fetch, CDP server with
Puppeteer/Playwright examples, localhost / private-network opt-in,
scaling profile, and known limits.
* docs(skills): address review feedback
- Remove --allow-private-network and OBSCURA_ALLOW_PRIVATE_NETWORK examples (not on main)
- Drop "screenshot" trigger word; Obscura doesn't support screenshots (#37, #123)
- Reword Known Limits: screenshots are not implemented, not low-fidelity