Add owned YED evaluators and a direct typed native boundary

[Hancapo]

Summary

• Add immutable YedEvaluator snapshots from Yed.compile(...), retaining the public typed result, unresolved-expression/native-attachment diagnostics and explicit caller-owned variables.
• Pass typed input values directly to the native boundary and build final Vector4 outputs there. Matching output/final-track values share immutable objects within one frame.
• Preserve a fresh native frame per evaluation and release the GIL during VM work. Compiled evaluators retain no mutable YED or skeleton.
• Correct the mutable convenience cache to compare full executable/default content, including in-place operand and skeleton edits, rather than incomplete object identities and lengths.

Verification

• Public/compiled equivalence tests cover typed and iterable inputs, diagnostics, detached lifetime, in-place edits, defaults, stateless seeks, concurrent actors and explicit variable persistence.
• Uninstrumented synthetic evaluation measured 1.039 ms/frame for the pre-change public path and 0.480 ms/frame for the compiled evaluator, about 2.2x faster. Current mutable evaluation costs 1.280 ms/frame because it now checks complete source content. Repeated playback must compile once to obtain the improvement.
• The supplied profile identifies substantial conversion and repeated expression-resolution work; overlapping profile totals are not added together or translated into FPS claims.

Based on #299. No consumer code or installed packages changed. No merge or release requested for this stack.