feat: Add phase-by-phase prompt generation for complex projects

- Generate prompts/phase{1-4}-prompt.txt files with phase-specific tasks
- Update GUIDE.md with phase-by-phase execution instructions
- Include both /ralph-wiggum and bash loop alternatives for each phase
- Each phase prompt references PROMPT.md and focuses on one phase only
- Add tech-stack-specific build/test/lint commands per phase

Also includes fix for JSON parsing with markdown code fences.

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

progress.txt

@@ -125,3 +125,41 @@
   9. README.md documents all commands and options ✓
   10. npm publish --dry-run succeeds ✓
 
+[2026-01-11T03:21:00Z] [5] [FIX] - Fixed JSON parsing for Claude responses wrapped in markdown code fences
+  - Added stripCodeFences() utility function to src/utils/files.ts
+  - Updated src/generators/specification.ts to use stripCodeFences
+  - Updated src/clients/claude.ts in 3 places:
+    * parseArchitectureResponse()
+    * parseQueriesResponse()
+    * generateSpec()
+  - The new approach handles edge cases better than the regex match approach
+  - Build and all 110 tests pass
+
+[2026-01-11T04:37:00Z] [6] [FEATURE] - Phase-by-phase prompt generation
+  - Modified src/generators/scaffold.ts:
+    * Added prompts/ directory creation
+    * Added writePhasePrompts() method to generate 4 phase-specific prompt files
+    * Added generatePhasePrompt() to create individual phase prompts
+    * Added helper methods for build/test/lint commands per language
+    * Updated dry-run structure logging to include prompts/
+  - Modified src/generators/prd.ts:
+    * Rewrote generateGuideMd() to generate deterministic phase-by-phase guide
+    * GUIDE.md now includes 4 phases with:
+      - /ralph-wiggum:ralph-loop command for each phase
+      - Verification command after each phase
+      - Bash loop alternative for each phase
+    * Still includes full project execution as alternative
+  - Updated test in src/__tests__/prd.test.ts to match new GUIDE.md format
+  - Generated files:
+    * prompts/phase1-prompt.txt - Foundation phase
+    * prompts/phase2-prompt.txt - Core phase
+    * prompts/phase3-prompt.txt - Integration phase
+    * prompts/phase4-prompt.txt - Polish phase
+  - Each phase prompt includes:
+    * Reference to PROMPT.md for context
+    * Phase-specific tasks from prd.json
+    * Working instructions with tech-stack-specific commands
+    * Phase-specific completion promise (PHASE_X_COMPLETE)
+  - Build succeeds, all 110 tests pass, lint clean
+  - Tested with ralph-vibe new word-counter - all phase files generated correctly
+