Package transformation frontends for Python v0.4.0

[TonisOrmisson]

What changed

• keeps canonical transformation plans, schema models, and live-schema validation language-neutral
• moves the SPSS lexer/parser/binder/compiler into openstatspec.frontends.spss
• adds a generic apply_transformation_plan_in_place API for typed plans and strict mappings
• keeps compile_spss_syntax, apply_spss_in_place, legacy transform imports, and apply-spss compatible
• adds apply-plan and install-in-place-schema CLI commands
• reserves empty Stata and SAS frontend directories without support claims
• records canonical-plan versus SPSS-source audit provenance
• documents the architecture and operational workflow in a transformation manual linked from README
• prepares package version 0.4.0 and release gates

Why

The previous implementation had a generic canonical plan but placed SPSS-specific parser/compiler files under the generic transform namespace, and the SQL executor compiled SPSS text itself. This made future frontends difficult to add safely.

The new boundary is source syntax → frontend → canonical plan → generic in-place executor.

Invariants

• same logical dataset and physical wide table are mutated in place
• no OpenStatSpec undo, snapshot, copied table, derived dataset, or parallel history layer
• all supported SQL connections remain allowed
• Dolt adds branch/HEAD/clean-working-set controls and remains the versioning layer

Validation

• complete local test suite: passed
• focused canonical/frontend/in-place/CLI suite: 40 passed
• official specification conformance fixtures: passed
• source and installed-wheel import/compatibility smoke: passed
• wheel and sdist builds: passed
• two independent autoreview loops: no remaining P0/P1 blockers
• git diff --check: passed (line-ending notices only)

[chatgpt-codex-connector]

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[chatgpt-codex-connector]

Preserve operation spans in SPSS binding results

When callers compile SPSS syntax and inspect compilation.bound.operation_spans, this return now replaces the previous SPSS bound result with the generic two-field BoundTransformation, causing an AttributeError and discarding the spans collected above. Preserve the tuple in a frontend-specific result (or expose it on SpssFrontendCompilation) so the existing source-to-operation mapping remains available.

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