fix: harden degraded source handling

apis/briefing.mjs

@@ -61,12 +61,13 @@ export async function runSource(name, fn, ...args) {
     const hasError = Boolean(data?.error);
     const degradedStatuses = ['no_credentials', 'no_key', 'disabled', 'degraded', 'failed', 'error'];
     const isDegraded = hasError || degradedStatuses.includes(data?.status);
+    const error = data?.error || data?.configWarning || data?.message || null;
     return {
       name,
       status: isDegraded ? 'degraded' : 'ok',
       durationMs: Date.now() - start,
       data,
-      error: hasError ? data.error : null,
+      error: isDegraded ? error : null,
     };
   } catch (e) {
     return { name, status: 'error', durationMs: Date.now() - start, error: e.message };