Add basic MySQL TLS support

[Johno-ACSLive]

Summary

This PR adds minimal, opt‑in TLS support for MySQL connections in Nginx Proxy Manager. It introduces three environment variables:

Variable	Default	Purpose
DB_MYSQL_SSL	false	Enable SSL when set to true.
DB_MYSQL_SSL_REJECT_UNAUTHORIZED	true	Controls certificate chain validation.
DB_MYSQL_SSL_VERIFY_IDENTITY	true	Enables hostname verification.

No behavior changes for existing users unless DB_MYSQL_SSL is explicitly enabled. Does not impact other DB engine configuration.

Motivation

Environments such as:

• Azure Database for MySQL (secure transport enforced)
• Self-hosted MySQL with require_secure_transport=ON
• Security baselines requiring encrypted DB connections

…currently cause startup failure (ER_SECURE_TRANSPORT_REQUIRED) because connection attempts are plaintext. This update allows secure connections while remaining completely backward compatible.

Backward Compatibility

Scenario	Before	After
No TLS vars set	Plain MySQL	Same
Server requires TLS; no vars set	Startup error	Same (user must enable SSL)
TLS enabled (DB_MYSQL_SSL=true)	N/A	Encrypted session
Self-signed cert (user sets DB_MYSQL_SSL_REJECT_UNAUTHORIZED=false)	N/A	Connects (user-accepted risk)
Hostname mismatch & DB_MYSQL_SSL_VERIFY_IDENTITY=true	N/A	Fails (correct security posture)

Out of Scope / Future Work

• Optional CA / client certificate path variables
• Min/Max Cipher and associated checks
• Postgres TLS parity (could mirror same pattern)

[nginxproxymanagerci]

CI Error:

/bin/bash: warning: setlocale: LC_ALL: cannot change locale (en_US.UTF-8)
certbot-node: Pulling from nginxproxymanager/nginx-full
Digest: sha256:673f9b213c376058b694c70ef80666098f215cf573cb557c32afd4124f0cbd1b
Status: Image is up to date for nginxproxymanager/nginx-full:certbot-node
docker.io/nginxproxymanager/nginx-full:certbot-node
�[1;34m❯ �[1;36mBuilding Frontend ...�[0m
yarn install v1.22.22
[1/4] Resolving packages...
[2/4] Fetching packages...
error Error: https://registry.yarnpkg.com/source-map/-/source-map-0.6.1.tgz: Request failed "500 Internal Server Error"
    at ResponseError.ExtendableBuiltin (/usr/lib/node_modules/yarn/lib/cli.js:696:66)
    at new ResponseError (/usr/lib/node_modules/yarn/lib/cli.js:802:124)
    at Request.<anonymous> (/usr/lib/node_modules/yarn/lib/cli.js:66750:16)
    at Request.emit (node:events:519:28)
    at module.exports.Request.onRequestResponse (/usr/lib/node_modules/yarn/lib/cli.js:142287:10)
    at ClientRequest.emit (node:events:519:28)
    at HTTPParser.parserOnIncomingClient (node:_http_client:716:27)
    at HTTPParser.parserOnHeadersComplete (node:_http_common:121:17)
    at TLSSocket.socketOnData (node:_http_client:558:22)
    at TLSSocket.emit (node:events:519:28)
info Visit https://yarnpkg.com/en/docs/cli/install for documentation about this command.