Refactor ephemeral message handling in ticket interactions

- Updated ticket command and interaction responses to utilize the new `ephemeral()` function for consistent ephemeral message handling.
- Enhanced error handling for member fetching in ticket interactions, ensuring proper responses when members are not found.
- Improved localization for new error messages related to member presence in ticket commands.
- Documented changes in phase tracking to reflect updates in ticket interaction responses.

apps/bot/src/modules/tickets/service.ts

@@ -71,6 +71,15 @@ export class TicketPanelError extends Error {
   }
 }
 
+function isUnknownChannelError(error: unknown): boolean {
+  return Boolean(
+    error &&
+      typeof error === 'object' &&
+      'code' in error &&
+      (error as { code: unknown }).code === 10003
+  );
+}
+
 function botCanPostPanel(
   channel: GuildBasedChannel,
   meId: string
@@ -707,7 +716,11 @@ async function fetchTicketMessages(
         timestamp: message.createdAt.toISOString()
       }));
   } catch (error) {
-    logger.warn({ error, ticketId: ticket.id }, 'Failed to fetch ticket messages');
+    if (isUnknownChannelError(error)) {
+      logger.debug({ ticketId: ticket.id }, 'Ticket channel already gone while fetching messages');
+    } else {
+      logger.warn({ error, ticketId: ticket.id }, 'Failed to fetch ticket messages');
+    }
     return [];
   }
 }
@@ -1123,7 +1136,11 @@ export async function closeTicket(
         await channel.delete(`Ticket ${ticket.id} closed`);
       }
     } catch (error) {
-      logger.warn({ error, ticketId: ticket.id }, 'Failed to delete ticket channel');
+      if (isUnknownChannelError(error)) {
+        logger.debug({ ticketId: ticket.id }, 'Ticket channel already gone while deleting');
+      } else {
+        logger.warn({ error, ticketId: ticket.id }, 'Failed to delete ticket channel');
+      }
     }
   }
 }