feat(agent): harness adapter ('connect a Claude/Codex subscription') + driving loop

[JSONbored]

Parent epic: #770 (Phase 2).

Goal

Extend init-client into a first-class auto-dev profile that wires the local harness (Claude Code/Codex/Cursor) to the gittensory MCP + miner-planner profile + a plan→implement→push driving loop.

Deliverables

• auto-dev profile generator (per harness)
• Driving loop: decision_pack → reward_risk → pick action → local_branch plan → (harness implements) → N8 write-tools push
• Reward-aware: respect open-PR gate, credibility floor, time-decay

Context

packages/gittensory-mcp/bin (init-client, agent profiles), src/services/decision-pack.ts, reward-risk.ts.

Milestone: M4.