Add web UI, sender profiles, purge rules, and infosec action

Extends the pipeline with infosec classification, sender profile tracking,
and configurable purge rules. Adds a web dashboard for managing rules and
monitoring email processing. Includes new migrations and seed script.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

pyproject.toml

@@ -33,6 +33,11 @@ dependencies = [
     "tenacity>=9.0.0",
     # HTML stripping for email bodies
     "beautifulsoup4>=4.12.0",
+    # Web UI
+    "fastapi>=0.115.0",
+    "uvicorn[standard]>=0.32.0",
+    "jinja2>=3.1.0",
+    "python-multipart>=0.0.12",
 ]
 
 [project.scripts]