19. A Plain Call Path for Unmemoized Rules Without Captures

• A rule call went through call → invoke → invokeBegin / body / invokeEnd: a capture frame was allocated or shared and switched to, an invokeState was built and copied, and the failure handling of call came on top. In profiles of recognition this chain was about a fifth of the time.
• An unmemoized call (transient rules, and first calls since change 18) of a rule whose scope has no captures now goes through invokePlain, which does the same steps inline and leaves the caller's frame current (a body without captures never writes one). Depth limit, cut, environment, trail, recovered errors and finish behave as before. The closure backend and the recursive VM use it; the iterative VM has its own call frames.
• Effect (min of 6 interleaved runs, Apple M3 Max): full parses 2.5–9.5% faster (JSON closure 17.7 → 16.5 ms, bytecode 21.8 → 19.8 ms; XML closure 17.8 → 16.2 ms), recognition 5.5–15.6% faster (JSON closure 11.8 → 10.0 ms, bytecode 16.4 → 13.8 ms).