Add watch mode for automatic processing

[celloopa]

Overview

Optional watch mode that monitors the postings folder and auto-processes new files.

Usage

# Start watch mode
ghosted watch

# With options
ghosted watch --dir local/postings
ghosted watch --auto-approve
ghosted watch --notify  # Desktop notification on completion

Behavior

1. Watch local/postings/ for new files
2. Ignore files starting with . or in processed/
3. On new file detected:
   • Run full agent pipeline
   • If approved: move to processed/
   • If rejected: move to needs-review/ with feedback file

Implementation Options

1. fsnotify: Go library for filesystem events
2. Polling: Simple periodic directory scan

Priority

This is a "nice to have" - implement after core pipeline works.

Testing

• Test file detection logic (ignore dot files, processed/)
• Test fsnotify/polling event handling
• Test pipeline trigger on new file
• Test file move to processed/ or needs-review/
• Test graceful shutdown