types: declare caller option on TransportBaseOptions

[lx3133584]

Problem

While caller is supported by pino.transport and documented in docs/api.md for framework integrations requiring custom caller resolution, passing caller to pino.transport(...) or pino({ transport: { caller: ... } }) resulted in a TypeScript compilation error because caller was omitted from TransportBaseOptions in pino.d.ts.

Cause

TransportBaseOptions declared options and worker properties, but did not declare caller?: string | string[], causing TypeScript to reject object literals containing caller due to excess property checks on TransportSingleOptions, TransportMultiOptions, and TransportPipelineOptions.

Fix

• Added caller?: string | string[] to pino.TransportBaseOptions in pino.d.ts.

Testing

• Added type assertions in test/types/pino-transport.tst.ts covering pino.transport with single and multiple targets as well as pino({ transport: { ... } }) with string and string array caller options.
• Verified npm run test-types passes cleanly across all targets with attw verification.