refactor(s3control): eliminate goofy source files, split giant files Pure reorganization, behavior identical (verbatim moves, wire shapes byte-identical). backend_batch1/2/3 + handler_batch1/2/3 + handler.go (2466) split into op-family files (models.go, errors.go, backend_<family>.go, handler_<family>.go; max 746). 9 goofy test files (batch1-4/coverage/refinement1/parity_pass5-7) consolidated into per-family test files (154->154 tests, 156->156 subtests preserved); stripped goofy Test prefixes. No funlen/gocyclo nolints (none existed); zero new nolint. Whole package green (build/test-race/vet/fix/gofmt/lint 0 issues). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

refactor(s3control): eliminate goofy source files, split giant files Pure reorganization, behavior identical (verbatim moves, wire shapes byte-identical). backend_batch1/2/3 + handler_batch1/2/3 + handler.go (2466) split into op-family files (models.go, errors.go, backend_<family>.go, handler_<family>.go; max 746). 9 goofy test files (batch1-4/coverage/refinement1/parity_pass5-7) consolidated into per-family test files (154->154 tests, 156->156 subtests preserved); stripped goofy Test prefixes. No funlen/gocyclo nolints (none existed); zero new nolint. Whole package green (build/test-race/vet/fix/gofmt/lint 0 issues). Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com> #6941