Add Felan Code to the ACP Registry

[mslavov]

Summary

Adds Felan Code (felan), Felan's open-source, model-portable coding agent, to the ACP Registry.

Distribution

• npm package: @felan-ai/felan@0.24.4
• ACP launch: npx --yes @felan-ai/felan@0.24.4 acp
• Terminal authentication: felan acp login (["login"] is appended to the configured ACP command)
• License: MIT
• Icon: 16×16 monochrome currentColor adaptation of the canonical Felan brand mark

Validation

• Felan release workflow passed, including pnpm verify, packed audit, and npm publish
• Published npm tarball includes the felan binary, compiled ACP modules, and SLSA provenance
• uv run --with jsonschema .github/workflows/build_registry.py --dry-run
• python3 .github/workflows/verify_agents.py --auth-check --agent felan
• Live initialize checks passed for the Registry terminal-auth payload and stabilized ACP v1 terminal-auth capability
• Workflow Ruff checks and all 194 workflow tests passed