Add gastown postPatch bug fixes from jt flake

- Fix mail router normalization in validateRecipient
- Fix agentBeadToAddress to use title field for hq- prefixed beads
- Fix crew/polecat home paths (remove incorrect /rig suffix)
- Fix town root detection (RoleUnknown instead of RoleMayor)
- Fix copyDir symlink handling
- Pin to gastown commit 177094a matching jt flake

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

flake.lock

@@ -81,11 +81,11 @@
     "gastown": {
       "flake": false,
       "locked": {
-        "lastModified": 1769402003,
-        "narHash": "sha256-9jW0s/bqDIcWAf7ReYXhhPU5EQS0MNHVNlyYVnopORE=",
+        "lastModified": 1769538736,
+        "narHash": "sha256-A33gyS/ERUCFcaFG9PJdIHfIOafguqkRe+DuIZteH5s=",
         "owner": "steveyegge",
         "repo": "gastown",
-        "rev": "baec5b6147eed8c63a0b4cef3529b4ebb520e910",
+        "rev": "177094a2335786d1d450fd9e14b935877291c004",
         "type": "github"
       },
       "original": {