fix: support Memos API identity migration

app/api/sources/route.ts

@@ -22,7 +22,9 @@ export async function POST(req: Request) {
     }
     const shared = db.prepare("SELECT id FROM sources WHERE base_url=? AND remote_user=?").get(baseUrl, identity.name) as { id: number } | undefined;
     if (shared) { db.prepare("INSERT OR IGNORE INTO source_members(source_id,user_id) VALUES(?,?)").run(shared.id, user.id); return NextResponse.redirect(externalUrl(req, "/dashboard?source=shared")); }
-    const name = identity.nickname || identity.username || identity.name;
+    const name = identity.displayName || identity.nickname || identity.username || identity.name;
+    const existing = db.prepare("SELECT id FROM sources WHERE user_id=? AND base_url=?").get(user.id, baseUrl) as { id: number } | undefined;
+    if (existing) { db.prepare("UPDATE sources SET name=?,token_encrypted=?,remote_user=?,sync_status='queued',last_connection_error=NULL WHERE id=?").run(name, encrypt(token), identity.name, existing.id); queuePull(existing.id, "source-created"); return NextResponse.redirect(externalUrl(req, "/dashboard?source=reconnected")); }
     const out = db.prepare("INSERT INTO sources(user_id,name,base_url,token_encrypted,remote_user,sync_status) VALUES(?,?,?,?,?, 'queued')").run(user.id, name, baseUrl, encrypt(token), identity.name);
     const sourceId = Number(out.lastInsertRowid);
     db.prepare("INSERT INTO source_members(source_id,user_id,role) VALUES(?,?,'owner')").run(sourceId, user.id);