- Add DispatchContext field to Task model for rule metadata storage
- Add BlocklistEmails config (BLOCKLIST_EMAILS env var)
- Wire rules.Pipeline into IMAPWatcher, replacing inline whitelist check
- Pass rule metadata through DispatchContext to OpenClaw dispatch
- Remove isWhitelisted method (now handled by WhitelistRule)
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>