Honor @field(name:) in @error payload construction shape resolution

FieldBuilder.resolvePayloadConstructionShape (FieldBuilder.java:506-609) picks an @error payload class’s construction shape, then the emitter (catch-arm payloadFactoryLambda in TypeFetcherGenerator, and the validator pre-step’s declareEarlyPayloadFromErrors) generates either an all-fields-ctor invocation or a no-arg-ctor + per-SDL-field setter sequence against it. Neither arm reads @field. The mutable-bean arm at :589-591 matches set<UcFirst(sdlFieldName)> on payloadCls.getMethods() via the Java-bean conversion in javaBeanSetterName; the classifier’s existing invariant at :498-505 pins "setter method name matches the SDL field name under Java-bean conversion" as a contract the emitter relies on. The all-fields-ctor arm at :519-535 picks the single ctor whose parameter count equals sdlFieldNames.size() and the emitter then assumes positional alignment with SDL declaration order. Either way, a payload class whose Java component or setter names diverge from the SDL field names has no remap ; exactly the shape R191 now admits on data fields. The fix is to thread @field(name:) on each SDL field into both arms: in the mutable-bean arm, derive the setter base from the directive value when present (set<UcFirst(directiveName)>) and persist the SDL-to-Java mapping on SetterBinding; in the all-fields-ctor arm, the directive value picks the matching parameter (by name where the ctor exposes parameter names, otherwise by the directive’s positional alignment with the record component / canonical-ctor parameter order). Update the classifier invariant text at :498-505 to reflect the new contract (setter / parameter name matches the directive value when present, the SDL field name otherwise). This is the output-side mirror of R200; together they restore symmetry across input bean / record binding (R200) and output payload bean / record construction (this item).