Add GitAgent Protocol support (agent.yaml + SOUL.md)

[shreyas-lyzr]

Hi! 👋 This PR adds GitAgent Protocol support to Browser Use Web UI — a small, open standard that makes AI agents portable and discoverable.

What this adds (nothing else is touched):

• agent.yaml — a standard manifest declaring the agent's name, version, model preferences, skills, and compliance posture
• SOUL.md — the agent's persona and behavioural instructions in the canonical GAP format

With these two files, Browser Use Web UI can run on any GAP-compatible runtime and be listed on the Open GAP Registry, making it easier for users to discover and deploy it.

Everything here is a proposal — totally fine to tweak the fields or close if it's not a fit. The files only add to the repo; nothing existing is changed. 🙏

🔗 Learn more: https://gitagent.sh

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Summary by cubic

Adds GitAgent Protocol support by introducing agent.yaml and SOUL.md. This makes Browser Use Web UI portable to GAP-compatible runtimes and eligible for the Open GAP Registry.

• New Features
  • agent.yaml: manifest with name/version, model prefs (openai:gpt-4o, fallbacks anthropic:claude-sonnet-4-6, google:gemini-2.0-flash), skills, runtime limits, and compliance (human_in_the_loop: destructive, kill_switch: true).
  • SOUL.md: canonical persona and behavior with two modes (Browser Agent, Deep Research), constraints, and safety posture.
  • Purely additive; no existing files changed.

^{Written for commit 07db6f9. Summary will update on new commits. Review in cubic}

[CLAassistant]

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[cubic-dev-ai]

No issues found across 2 files

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