🦭 Implement Certificate Authority

[teon]

• Research rust libraries to generate own CA
• Issue certificates based on CSRs
• Implement Proxy to create CSRs
• Implement initial handshake with Core that setups certificates in Proxy (if it doesn't already have certificates)
• Handle graceful restart of either Core or Proxy
• Persist all certificates/keys in Core
• Persist all certificates/keys in Proxy
• Make sure that when core/proxy restarts after certificate setup, the communication automatically switches to HTTPS and skips the handshaking phase
• Error handling in Proxy, consider edge cases
• Error handling in Core, consider edge cases
• Prepare the feature for a HA environment
• Make sure any errors during the setup are propagated to Core

Not planned:

• Launch HTTPS with own cert for "aditional" (without reverse-proxy)