Rust target selection and original random-state update

RE-859. Reproduce with python3 scripts/analyze_rust_target_pick.py; focused validation: cargo xtask test-group rust-target-pick. Machine report.

Rust matches 168 original target selections and five six-step RNG sequences. It preserves first32-match collection, actual xorshift word transitions, single conditional draw, modulo selection and null/missing diagnostic intentions. Native initialization, message rendering and live world ownership remain open.

Original executable/native runtime and complete Linux/macOS Rust/Bevy/Solari acceptance remain unverified.