Stop Matrix refresh loop when login is unavailable

src/services/chat/service.ts

@@ -25,6 +25,13 @@ export interface TokenRefresher {
   refresh(): Promise<void>;
 }
 
+class MatrixAuthenticationUnavailableError extends Error {
+  constructor(cause: unknown) {
+    super('Matrix authentication could not be restored', { cause });
+    this.name = 'MatrixAuthenticationUnavailableError';
+  }
+}
+
 /**
  * Optional Reddit-API hook for resolving t2 IDs to real usernames. Without
  * it, conversations show up as `t2_abc123` (stable but ugly). With it, the
@@ -174,7 +181,11 @@ export class ChatService {
     } catch (err) {
       if (err instanceof MatrixAuthError && this.tokenRefresher) {
         this.logger.warn('[chat] Matrix token rejected — refreshing via browser session');
-        await this.tokenRefresher.refresh();
+        try {
+          await this.tokenRefresher.refresh();
+        } catch (refreshError) {
+          throw new MatrixAuthenticationUnavailableError(refreshError);
+        }
         return await fn();
       }
       throw err;
@@ -331,6 +342,7 @@ export class ChatService {
           try {
             await this.loadDetails(chat);
           } catch (err) {
+            if (err instanceof MatrixAuthenticationUnavailableError) throw err;
             this.logger.error(`[chat] backfill: failed details for ${chat.roomName}`, err);
           }
           done++;
@@ -1062,6 +1074,10 @@ export class ChatService {
         }) as { state_key?: string } | undefined;
         t2 = otherMember?.state_key?.match(/^@(t2_[^:]+):/)?.[1];
       } catch (err) {
+        if (err instanceof MatrixAuthenticationUnavailableError) {
+          this.logger.warn('[chat] username enrichment paused until Reddit login is restored');
+          return;
+        }
         this.logger.debug(`[chat] /state lookup failed for ${chat.roomId}:`, err);
       }
       if (!t2) {
@@ -1074,6 +1090,10 @@ export class ChatService {
           )?.sender;
           t2 = otherSender?.match(/^@(t2_[^:]+):/)?.[1];
         } catch (err) {
+          if (err instanceof MatrixAuthenticationUnavailableError) {
+            this.logger.warn('[chat] username enrichment paused until Reddit login is restored');
+            return;
+          }
           this.logger.debug(`[chat] /messages lookup failed for ${chat.roomId}:`, err);
         }
       }