feat(core-consent): add handlers and consentRouter tRPC router

Protocol-agnostic handlers (grant, withdraw, isGranted, getCategories)
in core-consent/handlers/ call IConsent methods and return typed results.

consentRouter uses a consent-specific tRPC context (userId + consentFactory)
so each procedure can resolve the per-user IConsent instance at call time.
Auth middleware guards all four procedures and maps UnauthenticatedError →
UNAUTHORIZED via defineErrorMiddleware from core-shared (no local duplicate).

76 tests passing; new handler and router code at 100% branch coverage.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

packages/core-consent/src/index.ts

@@ -21,3 +21,22 @@ export {
   extractAnonymousConsent,
   migrateAnonymousConsent,
 } from "./migration";
+export { UnauthenticatedError } from "./entities/errors/consent";
+export {
+  grantHandler,
+  grantHandlerInputSchema,
+} from "./handlers/grant.handler";
+export type { GrantHandlerInput } from "./handlers/grant.handler";
+export {
+  withdrawHandler,
+  withdrawHandlerInputSchema,
+} from "./handlers/withdraw.handler";
+export type { WithdrawHandlerInput } from "./handlers/withdraw.handler";
+export {
+  isGrantedHandler,
+  isGrantedHandlerInputSchema,
+} from "./handlers/is-granted.handler";
+export type { IsGrantedHandlerInput } from "./handlers/is-granted.handler";
+export { getCategoriesHandler } from "./handlers/get-categories.handler";
+export { consentRouter } from "./consent.router";
+export type { ConsentRouter, ConsentRouterContext } from "./consent.router";