Fix private key import for JWT signing

- Use importPKCS8 to convert private key string to CryptoKey
- Pass CryptoKey to SignJWT.sign() instead of string
- Fix 'Key for RS256 algorithm must be CryptoKey' error

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

supabase/functions/create-google-meet-event/index.ts

@@ -30,11 +30,17 @@ interface CreateMeetRequest {
 // Function to create JWT and get access token
 async function getGoogleAccessToken(serviceAccount: GoogleServiceAccount): Promise<string> {
   try {
-    // Import JWT sign function from jose
-    const { SignJWT } = await import("https://deno.land/x/jose@v4.15.1/index.ts");
+    // Import JWT and crypto utilities
+    const { SignJWT, importPKCS8 } = await import("https://deno.land/x/jose@v4.15.1/index.ts");
 
     const now = Math.floor(Date.now() / 1000);
 
+    // Convert private key string to CryptoKey
+    const privateKey = await importPKCS8(serviceAccount.private_key, {
+      algorithm: 'RS256',
+      keyId: serviceAccount.private_key_id,
+    });
+
     // Create and sign JWT
     const token = await new SignJWT({
       iss: serviceAccount.client_email,
@@ -44,7 +50,7 @@ async function getGoogleAccessToken(serviceAccount: GoogleServiceAccount): Promi
       iat: now,
     })
       .setProtectedHeader({ alg: 'RS256', kid: serviceAccount.private_key_id })
-      .sign(serviceAccount.private_key);
+      .sign(privateKey);
 
     // Exchange JWT for access token
     const response = await fetch(serviceAccount.token_uri, {