smbc: frenzy generators

Ported InitEnemyFrenzy into src/core/enemyinit.c. The init jump table is now complete: ids $12 and $14–$17 no longer behave as NoInitCode.

• All five generators: LakituAndSpinyHandler (respawn after seven reappearance counts, or hatch a spiny in the frenzy object's own slot), InitFlyingCheepCheep, InitBowserFlame (both the SpawnFromMouth and right-extent paths), InitFireworks, and BulletBillCheepCheep (swimming cheep-cheep in water, bullet bill with the blast sound elsewhere)
• Shared helpers as statics: PlayerEnemyDiff, PlayerLakituDiff (with its lakitu speed side effects), PutAtRightExtent, FinishFlame, SetFlameTimer
• The BitMFilter vertical-position filter for the bullet bill / cheep-cheep generator, including the $ff reset and the bit scan
• CheckpointEnemyID exported from the interpreter — the generator's tail jumps there so the new enemy gets its own init
• Twelve data tables in src/data/enemies (the Bitmasks table already lived in data/scenery)
• Documented deviations: the star-flag scan leaves instead of the asm's deliberate infinite loop, and the fireworks table index is masked
• Nine new test scenarios in tests/core/enemyinit.c; full suite green (26 binaries)

Two commits: 8796458 (tables), f8979ed (generators). Next: RunEnemyObjectsCore and the per-frame enemy runners.