refactor(gastown): combine router.go patches into single file

Merge three separate patches that all modify internal/mail/router.go
into one combined patch to avoid patch ordering conflicts.

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

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

home/roles/development/default.nix

@@ -43,12 +43,8 @@ let
     # Bug fixes not yet merged upstream
     # Each patch is stored in a separate file for clarity and maintainability
     patches = [
-      # Fix validateRecipient bug: normalize addresses before comparison
-      ./gastown-fix-validate-recipient.patch
-      # Fix agentBeadToAddress to use title field for hq- prefixed beads
-      ./gastown-fix-agent-bead-address-title.patch
-      # Fix agentBeadToAddress to handle rig-specific prefixes (j-, sc-, etc.)
-      ./gastown-fix-agent-bead-rig-prefix.patch
+      # Combined mail router fixes: validateRecipient normalization, title field for hq- beads, rig prefixes
+      ./gastown-mail-router-fixes.patch
       # Fix crew/polecat home paths: remove incorrect /rig suffix
       ./gastown-fix-role-home-paths.patch
       # Fix town root detection: don't map to Mayor (causes spurious mismatch warnings)