chore: project cleanup and prepare for dual-track processing refactor

- Removed all test files and directories
- Deleted outdated documentation (will be rewritten)
- Cleaned up temporary files, logs, and uploads
- Archived 5 completed OpenSpec proposals
- Created new dual-track-document-processing proposal with complete OpenSpec structure
  - Dual-track architecture: OCR track (PaddleOCR) + Direct track (PyMuPDF)
  - UnifiedDocument model for consistent output
  - Support for structure-preserving translation
- Updated .gitignore to prevent future test/temp files

This is a major cleanup preparing for the complete refactoring of the document processing pipeline.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

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

.claude/settings.local.json

@@ -1,7 +1,15 @@
 {
   "permissions": {
     "allow": [
-      "Bash(git commit:*)"
+      "Bash(git commit:*)",
+      "Bash(xargs ls:*)",
+      "Bash(jq:*)",
+      "Bash(python:*)",
+      "Bash(python3:*)",
+      "Bash(source venv/bin/activate)",
+      "Bash(find:*)",
+      "Bash(ls:*)",
+      "Bash(openspec list:*)"
     ],
     "deny": [],
     "ask": []