fix: YouTube channel ID (UC...) handling + handle-to-channelId resolution

discover-channels: extractHandle('youtube') now detects UC* channel IDs
and returns them without @ prefix (previously @UC... caused verify fail)

verifyHandles: verifyYouTube uses cleanHandle for UC* check, requests
part=id,snippet for richer data

collect-channel-data: if channelId missing but handle present, resolves
via forHandle/forUsername lookup or direct UC* detection before skipping

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

supabase/functions/_shared/verifyHandles.ts

@@ -66,11 +66,11 @@ async function verifyYouTube(handle: string, apiKey: string): Promise<VerifiedCh
     }
 
     // Try as channel ID directly (starts with UC)
-    if (handle.startsWith('UC')) {
+    if (cleanHandle.startsWith('UC')) {
-      const res = await fetch(`${YT_BASE}/channels?part=id&id=${handle}&key=${apiKey}`);
+      const res = await fetch(`${YT_BASE}/channels?part=id,snippet&id=${cleanHandle}&key=${apiKey}`);
       const data = await res.json();
       if (data.items?.[0]) {
-        return { handle, verified: true, channelId: handle, url: `https://youtube.com/channel/${handle}` };
+        return { handle: cleanHandle, verified: true, channelId: cleanHandle, url: `https://youtube.com/channel/${cleanHandle}` };
       }
     }
 

supabase/functions/collect-channel-data/index.ts

@@ -109,7 +109,22 @@ Deno.serve(async (req) => {
     if (YOUTUBE_API_KEY && ytVerified?.verified) {
       tasks.push((async () => {
         const YT = "https://www.googleapis.com/youtube/v3";
-        const channelId = (ytVerified?.channelId as string) || "";
+        let channelId = (ytVerified?.channelId as string) || "";
+
+        // If no channelId, try to resolve from handle
+        if (!channelId && ytVerified?.handle) {
+          const h = (ytVerified.handle as string).replace(/^@/, '');
+          if (h.startsWith('UC')) {
+            channelId = h;
+          } else {
+            for (const param of ['forHandle', 'forUsername']) {
+              const lookupRes = await fetch(`${YT}/channels?part=id&${param}=${h}&key=${YOUTUBE_API_KEY}`);
+              const lookupData = await lookupRes.json();
+              channelId = lookupData.items?.[0]?.id || '';
+              if (channelId) break;
+            }
+          }
+        }
         if (!channelId) return;
 
         const chRes = await fetch(`${YT}/channels?part=snippet,statistics,brandingSettings&id=${channelId}&key=${YOUTUBE_API_KEY}`);

supabase/functions/discover-channels/index.ts

@@ -221,6 +221,8 @@ Deno.serve(async (req) => {
         h = h.replace(/^@/, '');
         // Reject if it looks like a non-YouTube URL
         if (h.includes('http') || h.includes('/') || h.includes('.com')) return null;
+        // Channel IDs start with UC — don't add @ prefix
+        if (/^UC[a-zA-Z0-9_-]{20,}$/.test(h)) return h;
         if (/^[a-zA-Z0-9._-]+$/.test(h) && h.length >= 2) return `@${h}`;
         return null;
       }