GHSA-w43h-r5m5-p832

### Summary The connection-test endpoint opened a raw TCP socket to the user-supplied database host without resolving and range-checking the destination, so private and link-local addresses (including IPv4-mapped IPv6 forms and `localhost`) reached the driver.

### Details A new `validateDbConnectionHost` helper resolves hostnames through DNS, parses each address with `ipaddr.js`, normalises IPv4-mapped IPv6, and rejects addresses in the private, loopback, link-local, unique-local, reserved, unspecified, broadcast, and carrier-grade-NAT ranges. `0.0.0.0`, `::`, and the literal `localhost` are special-cased. The check runs before the existing SSL block in the connection-test controller and gates the driver invocation.

### Impact Authenticated users with connection-test permission could probe internal services (Redis, the cloud metadata endpoint, internal databases) reachable from the NocoDB process. A DNS rebinding attacker could still race the resolve-vs-connect window.

### Credit This issue was reported by [@helwor-01](https://github.com/helwor-01).