feat(vnext): expose statement boundaries

[Light2Dark]

Summary

• expose synchronous, revision-stamped statementBoundaryAt and statementBoundariesIntersecting session queries
• preserve exact/no-code/opaque lexical states without leaking the private statement index
• add scanner-owned code spans that exclude separator trivia and form a strict hasCode discriminated union
• validate request envelopes as own data properties without invoking host accessors
• retain incremental index reuse and shift code spans with exact UTF-16 coordinates
• add public type, package smoke, hostile-input, affinity, opacity, masking, intersection, and documentation coverage

Verification

• 43 test files; 2,045 passed and 1 expected failure
• changed coverage: 97.92% statements, 96.12% branches, 100% functions, 98.07% lines
• all source/test/strict/loose/demo TypeScript configurations pass
• oxlint, test integrity, build, and runtime export smoke pass
• cold point lookup measured 3.59 ms at 1 MiB and 42.67 ms at the 16 MiB source ceiling; warm viewport intersection measured 0.075–0.096 ms
• two independent exact-head adversarial reviews approve c901544ff41480bb1e7ea2ddcab3af477dc8103f

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Summary by cubic

Expose synchronous, revision-stamped statement boundary queries in the vNext session API so editors and runners can locate executable SQL without re-lexing. Adds an exact/opaque boundary model with precise UTF-16 ranges and a code span for execution.

• New Features
  • Added session.statementBoundaryAt({ affinity, position }) and session.statementBoundariesIntersecting({ from, to }); results are frozen and include the current revision.
  • Exact boundaries expose extent, source, optional terminator, lexical endState, and a code span that excludes separator trivia; discriminated by hasCode.
  • Opaque boundaries report a reason for non-executable regions (procedural blocks, custom delimiters, resource limits).
  • All ranges map to the original document’s UTF-16 positions and respect masked embedded regions.
  • Inputs are strictly validated (own data properties only); invalid requests throw SqlSessionError with invalid-statement-boundary-request.
  • Exported new types via @marimo-team/codemirror-sql/vnext: SqlStatementBoundary*, SqlStatementAffinity, SqlStatementLexicalEnd, and related request/result shapes.

^{Written for commit c901544. Summary will update on new commits.}

[github-actions]

Coverage Report

Status	Category	Percentage	Covered / Total
🔵	Lines	98.07% (🎯 91%)	1119 / 1141
🔵	Statements	97.92% (🎯 91%)	1135 / 1159
🔵	Functions	100% (🎯 90%)	112 / 112
🔵	Branches	96.12% (🎯 85%)	918 / 955

File Coverage

File	Stmts	Branches	Functions	Lines	Uncovered Lines
Changed Files
src/vnext/index.ts	0%	0%	0%	0%
src/vnext/session.ts	98%	96.26%	100%	98.09%	156, 634, 677, 1108, 1146, 1228, 1555-1558, 1586-1590, 1690-1693, 1702-1708, 1715-1718, 1722-1726, 1794-1797, 2299-2302
src/vnext/statement-boundary-types.ts	0%	0%	0%	0%
src/vnext/statement-index.ts	97.68%	95.83%	100%	97.94%	286, 690, 889, 910, 1023, 1088-1090, 1100, 1112
src/vnext/types.ts	100%	100%	100%	100%

Generated in workflow #762 for commit c901544 by the Vitest Coverage Report Action