CIMVocabCheck: Local File Stores (RDF & CIMXML)

[spah-soptim]

Objective: Execute queries locally in memory against RDF or CIMXML files.

Description:
When the endpoint directive points to a local file (e.g., # [endpoint=./model.xml]), Jena should load and query it locally.

• Implement LocalStoreManager in the backend.
• Multi-File Support: Multiple directives create a union store (MultiUnion).
• Caching: Cache parsed graphs in a ConcurrentHashMap via CompletableFuture (LRU-bounded, max ~8 entries). Invalidate via mtime/size checks.
• Use the existing CimXmlParser for .xml and RDFDataMgr for .ttl, etc.
• Adjust SchemaManager logic: Instance data must not be mistakenly loaded as a validation schema.

Acceptance Criteria:

• Queries against local .xml and .ttl files execute correctly.
• Update queries (INSERT/DELETE) against local files are strictly rejected with UPDATE_NOT_ALLOWED.
• Modifying the target file invalidates the cache (mtime check verified).
• Documentation updated to cover local file and CIMXML querying.