LegacyPlateNesterAdapter.Create now delegates to PlateNesterFactory
instead of carrying its own minimal Default-only switch, so built-in
strategy resolution has one source of truth. Behavior unchanged:
unknown keys still reject; all four built-ins now resolvable.
44 net8.0 tests pass in Debug and Release; 0 warnings.
Replace name-based quantity deduction with reference-based drawing
identity in the engine paths the whole-job runner reaches
(NestEngineBase fill/pack, StripNestEngine deduction, RemnantFiller
ledger, IterativeShrinkFiller leftovers). Add instance-scoped
PlateNesterFactory that resolves built-in strategies without touching
the global NestEngineRegistry. Add identity and engine-selection tests.
44 net8.0 tests pass in Debug and Release; no new warnings.