refactor(verify): catalog G36 declaration requirements

[jscott3201]

Summary

• replace the two per-class checker branches with a private typed declaration catalog
• verify block members and enumeration literals through one fail-fast syntax path
• strengthen regression coverage for catalog order, short-circuiting, and exact diagnostics

Boundary

The public Rust function, CLI behavior, fixed source targets, check order, and error text remain unchanged. The catalog is private and in-memory; this PR adds no Python bridge, serialization, PyO3, cxf-json, dependency or workspace change, schema or registry change, generated artifact, dependency closure, inheritance, or semantic resolution.

Validation

• scoped rustfmt plus library and binary Cargo checks
• Rust tests — 22 passed
• pinned G36 declaration and source-inventory checks — 431 release and 693 development files
• routine lint suite — 189 passed
• fault replay — 137 fault directories and 1,760 scenarios passed
• dataset harness — 32 tests and the tiny FPU replay passed