v1.8.0: rewire compatibility

What changed

• Added position-aligned element type and shape metadata for every known node input and output.
• Included initializer tensor contracts in compatibility checks.
• Manual rewiring now rejects known element type, rank, and concrete dimension conflicts.
• Symbolic dimensions and missing metadata remain permissive.
• Rejected connections explain the conflict and do not add an edit-history entry.
• Successful rewires preserve source shape metadata on the replacement edge.

Verification

• 291 tests passed across 20 files.
• Lint and production build completed successfully.
• Verified in Chromium by attempting to connect a FLOAT source to an INT64 target and confirming the rejection message and unchanged history.