feat(vnext): add disposable completion info

[Light2Dark]

Summary

• expose an opt-in, type-safe completion info resolver on the vNext CodeMirror adapter
• give every resolver an AbortSignal and require explicit DOM resource cleanup
• abort pending work and destroy resolved UI on option, document, context, region, or view changes
• contain resolver/cleanup failures and reject cleanup reentrancy
• document the React-root integration pattern and export the public resolver types

Verification

• 43 test files; 2,036 passed and 1 expected failure
• changed coverage: 98.15% statements, 95.90% branches, 100% functions, 99.20% lines
• all strict/loose/demo TypeScript configurations pass
• oxlint and test-integrity checks pass
• build and runtime export smoke pass
• two independent exact-head adversarial reviews approve e07f8e525d6e6f2c7f73e24acd4e1f0b1ff90cc0

Stacked on #199, now merged into dev-refactor.

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Summary by cubic

Adds opt-in rich completion info to the vNext CodeMirror adapter. Introduces a type-safe infoResolver that returns a disposable DOM panel, with automatic abort and cleanup on selection or editor changes.

• New Features

  • autocomplete.infoResolver(item, { signal }) lets you render rich info and return { dom, destroy }; pending work is aborted and resolved resources are destroyed on option selection changes, document/context/region updates, or view disposal.
  • Stale results are ignored; null results omit the panel; resolver and cleanup failures are contained; reentrancy during cleanup is rejected.
  • Docs updated with a React root example; exported SqlCompletionInfoResolver, SqlCompletionInfoResolverContext, and SqlDisposableCompletionInfo from src/vnext/codemirror/index.ts.

• Migration

  • Opt in by passing sqlEditor({ autocomplete: { infoResolver } }).
  • Your resolver should use the provided AbortSignal and return { dom, destroy } or null.

^{Written for commit e07f8e5. Summary will update on new commits.}

[github-actions]

Coverage Report

Status	Category	Percentage	Covered / Total
🔵	Lines	99.2% (🎯 91%)	251 / 253
🔵	Statements	98.15% (🎯 91%)	266 / 271
🔵	Functions	100% (🎯 90%)	46 / 46
🔵	Branches	95.9% (🎯 85%)	164 / 171

File Coverage

File	Stmts	Branches	Functions	Lines	Uncovered Lines
Changed Files
src/vnext/codemirror/index.ts	0%	0%	0%	0%
src/vnext/codemirror/sql-editor.ts	98.15%	95.9%	100%	99.2%	200, 379, 445, 549, 553

Generated in workflow #760 for commit e07f8e5 by the Vitest Coverage Report Action