Polish Lynx Agent open-source presentation

[wangjiang314]

What changed

• Rewrites the README around Lynx Agent's completion-first Android phone-use positioning.
• Adds curated benchmark results and launch notes for GitHub About, topics, release notes, demos, and social posts.
• Tightens contributing, security, issue, and PR templates around verification, recovery, safety, and trace quality.
• Adds Android CI and includes the Gradle wrapper jar so clean clones can build and test.

Why

The public repo needed a clearer first-visitor story, stronger search keywords, credible benchmark evidence, and lower contributor friction. The main message is now explicit: a model saying finished is only a proposal; success is accepted after observable verification through VerifierAgent and CompletionGate.

Validation

• git diff --check HEAD~1 HEAD
• ./gradlew --version
• ./gradlew test --continue
• ./gradlew assembleDebug

Risk check

• Documentation and project packaging only; no runtime behavior changed.
• Benchmark results are presented as early engineering signals, not a leaderboard.
• Raw benchmark artifacts remain ignored because they can contain device-specific or provider details.