validate.rs: --strict silently ignored in APR validation path

[noahgift]

Bug

Two functions in validate.rs accept _strict: bool but never use it:

1. print_summary() at line 390: strict mode should make warnings cause failure
2. print_apr_validation_json() at line 234: strict should affect the passed JSON field

Note: strict IS properly used in run_rosetta_validation() (line 135-136) for non-APR formats. The bug is specific to the APR validation code path.

Root Cause

Parameters prefixed with underscore, silently discarded.

Expected Behavior

In strict mode, validation warnings (e.g., NaN, Inf, all-zero tensors) should cause failure in APR validation, matching the rosetta path behavior.

Fix

Add warnings for unimplemented strict behavior in APR path.

Found via kaizen dogfooding audit.