Implement Phase 3 & 4: Generation Pipeline and Polish

Phase 3 - Generation Pipeline:
- SpecificationGenerator: generates features, data models, interfaces
- PRDGenerator: generates PROMPT.md, prd.json, GUIDE.md, CLAUDE.md
- ScaffoldGenerator: creates complete project structure with git init
- Interactive prompts with Inquirer.js for user confirmation
- Full pipeline integration in new command

Phase 4 - Polish:
- Validate command for PROMPT.md files
- Standalone research command using Perplexity
- Dry-run mode with --dry-run flag
- Comprehensive README.md documentation
- Examples directory with sample outputs
- npm packaging verified (npm pack, npm publish --dry-run)

Bug fixes:
- Fix EXDEV error in atomic file writes (use same-dir temp files)
- Update Claude model to claude-sonnet-4-5-20250929

All 110 tests passing, all completion criteria met.

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

examples/README.md

@@ -0,0 +1,41 @@
+# Examples
+
+This directory contains sample files demonstrating ralph-vibe output.
+
+## Files
+
+### `test-idea.txt`
+
+A sample idea file that can be used with the `--idea-file` flag:
+
+```bash
+ralph-vibe new md2pdf --idea-file examples/test-idea.txt
+```
+
+### `sample-PROMPT.md`
+
+An example of a generated PROMPT.md file for a markdown-to-PDF converter CLI tool. Shows:
+- Project structure
+- User flow diagram
+- Feature specifications with acceptance criteria
+- Phase-based implementation plan
+- Completion criteria with verification commands
+- Promise tags for Ralph loop integration
+
+### `sample-prd.json`
+
+An example prd.json file showing the feature tracking structure.
+
+## Usage
+
+To test validation on the sample file:
+
+```bash
+ralph-vibe validate examples/sample-PROMPT.md
+```
+
+To generate a new project using the test idea:
+
+```bash
+ralph-vibe new test-project --idea-file examples/test-idea.txt --skip-confirm
+```