Fix crew worker mail identity mismatch (gt-2xiv)

Normalize crew/ and polecats/ to canonical form in addressToIdentity():
- gastown/crew/dave -> gastown/dave
- gastown/polecats/Toast -> gastown/Toast

Follows Postels Law: be liberal in what you accept.

internal/mail/types.go

@@ -276,13 +276,17 @@ func ParseMessageType(s string) MessageType {
 
 // addressToIdentity converts a GGT address to a beads identity.
 //
-// Addresses use slash format matching directory structure:
+// Liberal normalization: accepts multiple address formats and normalizes
+// to canonical form (Postel's Law - be liberal in what you accept).
+//
+// Addresses use slash format:
 //   - "mayor/" → "mayor/"
 //   - "mayor" → "mayor/"
 //   - "deacon/" → "deacon/"
 //   - "deacon" → "deacon/"
-//   - "gastown/polecats/Toast" → "gastown/polecats/Toast"
+//   - "gastown/polecats/Toast" → "gastown/Toast" (normalized)
-//   - "gastown/crew/max" → "gastown/crew/max"
+//   - "gastown/crew/max" → "gastown/max" (normalized)
+//   - "gastown/Toast" → "gastown/Toast" (already canonical)
 //   - "gastown/refinery" → "gastown/refinery"
 //   - "gastown/" → "gastown" (rig broadcast)
 func addressToIdentity(address string) string {
@@ -299,17 +303,25 @@ func addressToIdentity(address string) string {
 		address = address[:len(address)-1]
 	}
 
-	// Keep slashes - addresses map to directory structure
+	// Normalize crew/ and polecats/ to canonical form:
+	// "rig/crew/name" → "rig/name"
+	// "rig/polecats/name" → "rig/name"
+	parts := strings.Split(address, "/")
+	if len(parts) == 3 && (parts[1] == "crew" || parts[1] == "polecats") {
+		return parts[0] + "/" + parts[2]
+	}
+
 	return address
 }
 
 // identityToAddress converts a beads identity back to a GGT address.
 //
-// Identity format matches address format (slash-based):
+// Liberal normalization (Postel's Law):
 //   - "mayor/" → "mayor/"
 //   - "deacon/" → "deacon/"
-//   - "gastown/polecats/Toast" → "gastown/polecats/Toast"
+//   - "gastown/polecats/Toast" → "gastown/Toast" (normalized)
-//   - "gastown/crew/max" → "gastown/crew/max"
+//   - "gastown/crew/max" → "gastown/max" (normalized)
+//   - "gastown/Toast" → "gastown/Toast" (already canonical)
 //   - "gastown/refinery" → "gastown/refinery"
 func identityToAddress(identity string) string {
 	// Town-level agents ensure trailing slash
@@ -320,6 +332,11 @@ func identityToAddress(identity string) string {
 		return "deacon/"
 	}
 
-	// Identity already in slash format, return as-is
+	// Normalize crew/ and polecats/ to canonical form
+	parts := strings.Split(identity, "/")
+	if len(parts) == 3 && (parts[1] == "crew" || parts[1] == "polecats") {
+		return parts[0] + "/" + parts[2]
+	}
+
 	return identity
 }

internal/mail/types_test.go

@@ -13,9 +13,11 @@ func TestAddressToIdentity(t *testing.T) {
 		{"deacon", "deacon/"},
 		{"deacon/", "deacon/"},
 
-		// Rig-level agents: slash format matches directory structure
+		// Rig-level agents: crew/ and polecats/ normalized to canonical form
-		{"gastown/polecats/Toast", "gastown/polecats/Toast"},
+		{"gastown/polecats/Toast", "gastown/Toast"},
-		{"gastown/crew/max", "gastown/crew/max"},
+		{"gastown/crew/max", "gastown/max"},
+		{"gastown/Toast", "gastown/Toast"},         // Already canonical
+		{"gastown/max", "gastown/max"},             // Already canonical
 		{"gastown/refinery", "gastown/refinery"},
 		{"gastown/witness", "gastown/witness"},
 
@@ -44,9 +46,10 @@ func TestIdentityToAddress(t *testing.T) {
 		{"deacon", "deacon/"},
 		{"deacon/", "deacon/"},
 
-		// Rig-level agents: identity == address (slash format)
+		// Rig-level agents: crew/ and polecats/ normalized
-		{"gastown/polecats/Toast", "gastown/polecats/Toast"},
+		{"gastown/polecats/Toast", "gastown/Toast"},
-		{"gastown/crew/max", "gastown/crew/max"},
+		{"gastown/crew/max", "gastown/max"},
+		{"gastown/Toast", "gastown/Toast"},  // Already canonical
 		{"gastown/refinery", "gastown/refinery"},
 		{"gastown/witness", "gastown/witness"},