gh-106529: Cleanups split off gh-112134 (#112214)

- Double max trace size to 256
- Add a dependency on executor_cases.c.h for ceval.o
- Mark `_SPECIALIZE_UNPACK_SEQUENCE` as `TIER_ONE_ONLY`
- Add debug output back showing the optimized trace
- Bunch of cleanups to Tools/cases_generator/

Python/generated_cases.c.h

@@ -1731,6 +1731,7 @@
             seq = stack_pointer[-1];
             {
                 uint16_t counter = read_u16(&this_instr[1].cache);
+                TIER_ONE_ONLY
                 #if ENABLE_SPECIALIZATION
                 if (ADAPTIVE_COUNTER_IS_ZERO(counter)) {
                     next_instr = this_instr;