refactor(prompts): extract plan orchestrator prompts to separate files

Each prompt now lives in its own file under src/prompts/ for easier
editing and iteration. Includes index.ts for convenient re-exports.

chore: bump version to 0.1408

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

src/prompts/index.ts

@@ -0,0 +1,16 @@
+/**
+ * @fileoverview Plan Orchestrator Prompts
+ *
+ * Each prompt is in its own file for easy editing and iteration.
+ * Import from here for convenience.
+ */
+
+export { RESEARCH_AGENT_PROMPT } from './research-agent.js';
+export { REQUIREMENTS_ANALYST_PROMPT } from './requirements-analyst.js';
+export { ARCHITECTURE_PLANNER_PROMPT } from './architecture-planner.js';
+export { TESTING_SPECIALIST_PROMPT } from './testing-specialist.js';
+export { RISK_ANALYST_PROMPT } from './risk-analyst.js';
+export { CODE_REVIEWER_PROMPT } from './code-reviewer.js';
+export { VERIFICATION_PROMPT } from './verification.js';
+export { EXECUTION_OPTIMIZER_PROMPT } from './execution-optimizer.js';
+export { FINAL_REVIEW_PROMPT } from './final-review.js';