FulcrumSend MailBridge Phase 1 - ADDITIVE STARTER PATCH

What this adds:
- Connected mailbox table structure
- SMTP credential test/send engine using PHP streams
- Generated forwarding address creation
- Inbound raw email capture endpoint
- Basic inbound parser
- API endpoint for OpsHub to send through connected mailbox
- Webhook relay to OpsHub
- App dashboard starter pages
- Root installer/upgrader

Where to upload:
Upload and extract this ZIP inside your cPanel home/public_html area so the folders match your current subdomain document roots:

/public_html/app.fulcrumsend.com/
/public_html/api.fulcrumsend.com/
/public_html/inbound.fulcrumsend.com/
/public_html/fulcrumsend.com/
/fulcrumsend_phase1/

Install:
1. Edit /fulcrumsend_phase1/app/fs_config.php with your database credentials, app secret, and OpsHub webhook URL.
2. Visit: https://fulcrumsend.com/upgrade_mailbridge_phase1.php?token=YOUR_INSTALL_TOKEN
3. Delete or rename upgrade_mailbridge_phase1.php after successful install.
4. Open: https://app.fulcrumsend.com/mailbridge.php

Important:
- This does NOT magically configure DNS/MX/cPanel forwarding. It creates the software endpoints.
- For inbound receiving, create cPanel forwarders or default address routes to send mail to inbound.fulcrumsend.com endpoint/pipe based on your server setup.
- For production, move workers to a VPS/mail worker server where SMTP and inbound ports are allowed.
