Configure tested Firecrawl routing during launch

[hmishra2250]

Summary

Configures the experiment-validated Firecrawl routing state only during an authenticated first-use firecrawl launch journey for Claude Code and Codex.

The exact journey is:

firecrawl launch claude --project ./my-project --install --yes
firecrawl launch codex --project ./my-project --install --yes

After native MCP configuration and Firecrawl skill installation both succeed, the CLI:

• writes a versioned managed block to the project-local CLAUDE.md or AGENTS.md;
• adds the tested routing prefix to installed Firecrawl skill descriptions;
• preserves unrelated user-authored instructions;
• never writes a machine-global CLAUDE.md or AGENTS.md;
• does not deliver router state from package installation, init, direct setup mcp, MCP-only setup, skills-only setup, keyless setup, or unsupported harnesses.

This PR depends on #155 for secure native bearer MCP configuration.

User control and safety

• Default-on only inside the explicit firecrawl launch configuration journey.
• Opt out without changing routing state: --no-router-card.
• Remove the project card and exact Firecrawl skill prefixes: --remove-router-card.
• Project resolution prefers --project, then the containing Git worktree, then a safe current directory.
• Filesystem-root, home-directory, symlink, malformed-marker, and duplicate-marker writes fail closed.
• Writes are atomic, idempotent, preserve file mode and unrelated bytes, and refresh the skill lock after removal.

Experiment conclusion

EXP-029 reproduced the accepted combined state with native bearer MCP configuration and no forced Claude config flags.

• Decision: ship the launch state only
• Treatment: project context card + Firecrawl skill-description routing prefix
• Effectiveness: +87.5 percentage points
• 95% CI: +80.0 to +93.75 points
• Sign-flip p-value: ~1×10⁻⁶ with 1,000,000 permutations
• Claude Sonnet 5: +97.5 points
• Codex Terra: +77.5 points
• Safety: 0/100 treatment-only false hijacks per harness
• Simultaneous one-sided upper bound: 3.62%, below the 5% gate
• Analyzed spend: $45.43
• Complete clusters: 40/40 effectiveness and 100/100 safety
• Convex sessions: ax-orch-20260715-200438, ax-orch-20260715-201433, ax-orch-20260715-202753

Raw traces and judge outputs remain in Convex; no raw experiment results are committed.

Claim boundary: post-approval, authenticated launch state. The experiment does not measure human discovery or consent conversion.

Verification

• TypeScript typecheck passes.
• Full suite: 25 files / 401 tests passed.
• Build and npm package smoke pass.
• Real isolated Claude producer:
  • native https://mcp.firecrawl.dev/v2/mcp Authorization-header config;
  • project CLAUDE.md card;
  • all 31 currently shipped Firecrawl skills routed;
  • removal restores user bytes and all skill descriptions.
• Real isolated Codex producer:
  • native bearer_token_env_var = "FIRECRAWL_API_KEY" config;
  • project AGENTS.md card;
  • all 31 currently shipped Firecrawl skills routed;
  • removal restores user bytes and all skill descriptions.
• git diff --check passes.
• Commit history is one clear feature commit on top of Secure hosted MCP credential setup #155; no squash merge is requested.