Port gRPC server credential validation and settings

Bun corpus source

• js/third_party/grpc-js/test-server-credentials.test.ts
• sequential corpus position: 3991

Scope

• implement secure/insecure server credential objects and settings introspection
• preserve root CA and ordered key/certificate pairs
• validate runtime argument shapes and Buffer requirements
• provide stable field-aware errors with preserved causes and operation/source stacks
• add focused and permanent regression coverage

Tracking: #66

Implemented and published in 1a99c2e40 (feat(third-party): port gRPC server credentials).

What landed:

• secure/insecure server credential instances with _isSecure() and _getSettings() behavior
• root CA identity preservation and ordered key/certificate settings arrays
• client-certificate request/rejection settings
• exact runtime validation for root certs, key-pair arrays, pair objects, private keys, certificate chains, and boolean flags
• structured ERR_GRPC_SERVER_CREDENTIALS TypeErrors with exact field, preserved TypeError causes, and ServerCredentials.createSsl operation/source stack frames
• TypeScript import lowering and permanent diagnostic/third-party coverage

Verification:

• exact Bun file: 11 passed, 0 failed, 0 todo, 0 unsupported
• positions 3990–3991: 26 passed, 0 failed, 0 todo, 0 unsupported
• permanent gRPC diagnostics: 18 passed
• permanent SQL adapter and third-party mini-suite gates: passed
• formatting and diff checks: passed

Sequential corpus ledger through position 3991: 333 executable files, 2,817 passed, 213 upstream todos, 0 failed, 0 unsupported, 171 intentionally allowed-empty files.

Tracking: #66