Task 7 — Documentation updates for consolidated fix-path

[hiydavid]

Part of #179.

Goal

Update all documentation to reflect the consolidated Fix → Optimize model. Fix Agent removed from user-facing docs even though backend code remains (follow-up deletion under Workbench 0.2).

Work

• Handle docs/06-fix-agent.md: either delete outright OR keep with a "⚠️ Deprecated — see Auto-Optimize" banner at top. Decide during PR review.
• Update docs/07-auto-optimize.md:
  • Add new preflight IQ Scan stage (Stage 0 before Preflight, or renumber the 6-stage DAG to 7)
  • Document finding → lever mapping table
  • Document new genie_opt_scan_snapshots Delta table
  • Update architecture diagrams if any
• Update docs/appendices/A-api-reference.md:
  • Mark POST /api/spaces/{id}/fix as ⚠️ Deprecated — frontend no longer calls this (full removal tracked under Workbench 0.2)
  • Add any new fields to POST /api/auto-optimize/trigger and GET /api/auto-optimize/runs/{run_id}
• Update docs/00-index.md — remove Fix Agent entry from navigation
• Update README.md — remove Quick Fix mentions
• Update CLAUDE.md:
  • Replace "Two separate optimization paths" gotcha with the new consolidated model
  • Update the "Key Patterns" / "IQ Scan is the only analysis path" section to note scan is now also an Optimizer preflight input

Acceptance

• No mention of user-facing Quick Fix / Fix Agent workflow in docs 00-index, 07-auto-optimize, README, CLAUDE.md
• docs/06-fix-agent.md either removed or clearly marked deprecated
• Docs match the new behavior so a new contributor can trace the flow without surprise

Files

• docs/06-fix-agent.md
• docs/07-auto-optimize.md
• docs/00-index.md
• docs/appendices/A-api-reference.md
• README.md
• CLAUDE.md