…ccess tests

- Refactored binary persistency implementation to
  separate constants, low-level reader utilities.
- Fixed model header parsing to correctly handle
  model-reference kind vs model-id kind according
  to MPS binary persistency format.
- Correctly reconstruct model UUID with 'r:' prefix.
- Updated low-level test expectations to reflect fully-
  qualified model names.

… persistency and added low-level tests covering imports

… read_reference

- Integrated node loading into
  SModelBuilderBinaryPersistency
- Added root_nodes structure
- Extended tests to validate full model tree parsing

…rchitecture

- Removed registry dict usage
- Integrated index_2_* maps from base builder
- Construct real SConcept, SProperty, SNode instances
- Unified binary builder structure with XML persistency
- Updated tests to validate object-based model structure

- Implement full binary (.mpb) model parsing
- Load model header, registry, used languages and imports
- Build concept/property/reference/containment index maps
- Parse node tree including containment roles and properties
- Added support for reference kind validation and resolve_info
- Applied node id encoding during parsing
- Added repository-level completeness and resolution tests

…ode ids and also corrected existing test case failure

…nodes.py to fix the failing test