feat(vnext): add CodeMirror completion adapter

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Summary

• add an explicit @marimo-team/codemirror-sql/vnext/codemirror entry point with one caller-owned service and one session per EditorView
• translate composite CodeMirror document, context, and embedded-region effects into one atomic session update
• map current relation results to exact CodeMirror edits with revision, document, selection, context, and embedded-region guards
• coalesce exact-token catalog refreshes across active menus and empty loading results without synchronous provider-driven dispatch
• contain Escape, close, blur, visibility, expiry, service-first disposal, stale rejection, and repeated teardown races

Why

The framework-independent service now has the identity and lease contracts needed for a thin editor boundary. This adapter makes those contracts usable without leaking CodeMirror into the core, while preserving marimo's external completion sources and treating transformed-document regions explicitly rather than guessing their mapping.

Validation

• 2,028 tests pass; 1 intentional expected failure
• adapter coverage: 97.70% statements, 95.86% branches, 100% functions, 99.01% lines
• all strict and loose-optional TypeScript configurations pass
• oxlint and test-integrity checks pass
• packed-consumer source covers the new package subpath; hosted package CI will run the isolated install
• two independent exact-commit adversarial reviews approved 8d72a4c

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Summary by cubic

Adds a CodeMirror 6 adapter for the vNext SQL language service, exposed as @marimo-team/codemirror-sql/vnext/codemirror. This enables exact, guarded completion edits and atomic document/context/region updates without leaking CodeMirror into the core.

• New Features

  • New sqlEditor adapter with one document session per EditorView; caller owns the shared service.
  • Atomic updates: merges document changes with support.contextEffect and support.embeddedRegionsEffect.
  • Exact completion edits with revision/context/selection guards; maps unrelated embedded regions through its own edit; ignores overlaps.
  • Coalesced refresh intents keyed by service tokens; cancels on Escape, blur (configurable), visibility loss, selection change, or lease expiry; no synchronous provider-driven dispatch.
  • Single autocompletion configuration; supports externalSources for extra providers.
  • New docs: docs/vnext/codemirror-adapter.md; subpath export added in package.json; smoke test updated.

• Migration

  • Import from @marimo-team/codemirror-sql/vnext/codemirror, create a service from @marimo-team/codemirror-sql/vnext, then add support.extension to the editor.
  • Do not install a second autocompletion extension; pass extra providers via externalSources.
  • Update context/regions via support.setContext or by dispatching support.contextEffect and support.embeddedRegionsEffect. If embedded regions exist, include the complete resulting set on every document-changing transaction.

^{Written for commit 8d72a4c. Summary will update on new commits.}

[github-actions]

Coverage Report

Status	Category	Percentage	Covered / Total
🔵	Lines	99.01% (🎯 91%)	202 / 204
🔵	Statements	97.7% (🎯 91%)	213 / 218
🔵	Functions	100% (🎯 90%)	42 / 42
🔵	Branches	95.86% (🎯 85%)	139 / 145

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	97.7%	95.86%	100%	99.01%	187, 325, 391, 442, 446

Generated in workflow #758 for commit 8d72a4c by the Vitest Coverage Report Action