performance test suite

[aqk]

Note

Low Risk
Changes are limited to new tests and CI; the compiler and runtime behavior are unchanged.

Overview
Adds a compile performance regression harness and wires it into CI.

A new compile_performance_suite test compiles eight existing CLSP fixtures (program and module flows), records wall-clock compile time and compiled bytecode sizes, prints structured compile_perf lines to stderr, and only asserts that compilation succeeds with non-empty outputs—no timing or size thresholds yet.

A Performance GitHub Actions workflow runs that test in --release on pushes/PRs (plus workflow_dispatch), using Rust 1.97.1 and a 30-minute job timeout.

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