…handling (apache#11238)

This change introduces a new RepositoryAwareRequest interface that consolidates
repository handling across multiple Maven service request types, addressing
issues with duplicate repositories being passed to resolvers.

Key changes:

* Add RepositoryAwareRequest interface with repository validation:
  - Provides getRepositories() method and validate() logic
  - Prevents duplicate repositories and null entries
  - Consolidates common repository functionality

* Refactor service request interfaces to extend RepositoryAwareRequest:
  - ArtifactResolverRequest, DependencyResolverRequest, ModelBuilderRequest
  - ProjectBuilderRequest, VersionRangeResolverRequest, VersionResolverRequest
  - Apply repository validation in all implementations

* Fix repository leakage in DefaultProjectBuilder:
  - Store project-specific repositories in BuildSession
  - Implement proper repository merging based on strategy
  - Prevent cross-contamination between sibling projects

* Update resolvers to use toResolvingRepositories() for consistent handling

* Add RepositoryLeakageTest to verify proper isolation between projects

This eliminates duplicate repositories being sent to resolvers and ensures
consistent repository handling across all Maven service requests.

(cherry picked from commit f634360)