New module: document-scanner.js
- PDF: extracts text from content streams, scans for PPI, converts to
sanitized plaintext for upload (PDFs can't be reliably edited in-place)
- DOCX/XLSX: extracts text from XML entries, scans for PPI
- Text files: direct string substitution
- Handles scanned/image-only PDFs gracefully (skips with message)
Fetch interceptor (content.js):
- Now intercepts FormData uploads (file uploads) in addition to JSON
- Processes each file through document scanner
- Preview mode for PDF/DOCX/XLSX: shows PPI findings with counts,
user clicks "Substitute & Upload" or "Upload Original"
- Text files substituted silently (no preview friction)
- String form fields also substituted
- 30-second auto-dismiss on preview (uploads original if no response)
Preview UI (content.css):
- Centered overlay with dark theme matching existing warning UI
- Shows original → substituted pairs for each PPI found
- File format note (e.g. "PDF will be converted to plain text")
https://claude.ai/code/session_01SWSwDfMVij53bCTNSCLMwn