Fix email deliverability: send from SPF-verified subdomain

Emails were sent from noreply@octopodas.com but SPF record only exists
for send.octopodas.com. This caused emails to land in spam or be
rejected. Changed default from address to noreply@send.octopodas.com
which has proper SPF, DKIM, and DMARC records via Resend.

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

Author: RyjoxTechnologies

synrix_runtime/api/cloud_server.py

@@ -588,7 +588,7 @@ def _verify_code(email: str, code: str) -> bool:
 # Resend email integration
 # ---------------------------------------------------------------------------
 _RESEND_API_KEY = os.environ.get("RESEND_API_KEY", "")
-_RESEND_FROM = os.environ.get("RESEND_FROM_EMAIL", "Octopoda <noreply@octopodas.com>")
+_RESEND_FROM = os.environ.get("RESEND_FROM_EMAIL", "Octopoda <noreply@send.octopodas.com>")
 
 def _send_verification_email(email: str, first_name: str, code: str):
     """Send a verification code email via Resend."""