feat: implement CI (Continuous Intelligence) autonomous engineering harness

Implements the full PRD for CI - a fully autonomous AI-driven software
engineering harness derived from Learnship's architecture.

Core components:
- CI Orchestrator agent with autonomous pipeline (SPECIFY → CLARIFY →
  RESEARCH → PLAN → EXECUTE → VERIFY → COMPLETE)
- Decision Engine with confidence thresholds (high/medium/low)
- Clarify Phase with question budget and default acceptance
- Escalation Protocol with timeout auto-proceed
- Audit Trail system (.ci/audit/) for post-hoc review
- Error Recovery with retry, plan revision, and rollback

18 agents (all Learnship agents + Orchestrator):
- Autonomous behavioral modifications per PRD §7.1
- Agent registry with factory pattern

11 CLI commands:
- ci init, ci run, ci quick, ci debug, ci verify
- ci review, ci status, ci audit, ci clarify
- ci rollback, ci ship

4-layer verification system:
- Structural, Behavioral, Security, Code Quality

3 autonomy levels: full, supervised, guided
Compatible with Learnship artifact schemas (.planning/)

src/core/index.ts

@@ -0,0 +1,9 @@
+export { initCI, loadConfig, saveConfig, isCIInitialized, getCIConfigPath, getCIDir, ensureCIDir } from "./config.js";
+export { DecisionEngine } from "./decision-engine.js";
+export { EscalationProtocol } from "./escalation.js";
+export { ClarifyPhase, saveSpecification, loadSpecification } from "./clarify.js";
+export { ArtifactManager } from "./artifacts.js";
+export { ErrorRecovery } from "./error-recovery.js";
+export { logDecision, logEscalation, readAudit, getAuditSummary } from "./audit.js";
+export type { CIConfig } from "../types/config.js";
+export { DEFAULT_CI_CONFIG } from "../types/config.js";