Optionalchain: DER[]Optionalkey: PrivateKeyAuto-provision a self-signed certificate + private key
entirely in-memory using node-opcua-crypto/web.
If a cert+key pair was already provided at construction, this is a no-op.
No disk, no openssl, no node:fs.
Clears cached secrets.
Extends ICertificateKeyPairProvider with diagnostic file-location properties so that consumers can report where certificates are stored (real path or
"<in-memory>").Does not alter the public
ICertificateKeyPairProviderinterface — zero breaking change toServerSecureChannelParent,ClientSecureChannelParent, or any external implementation.