docs(providers): add capabilities, error handling, and usage examples to libsql doc

[De-pitcher]

Description

Brings \docs/providers/libsql.md\ in line with the standard provider doc structure (matching sibling docs such as \docs/providers/mongodb.md\ and \docs/providers/sqlite.md) by adding the missing Capabilities & labels, Error handling, and Usage examples sections, with verified content reflecting the actual libSQL provider implementation.

Type of Change

• Documentation update

Related Issue

Closes #862

Changes Made

• Added Section 9: Capabilities & labels documenting \getCapabilities()\ flags (\supportsExplain, \explainFormat, \supportsTransactions: false, \maintenanceOperations: [reindex, check], \containerLevels: [], \objectKinds) and custom \getLabels()\ overrides (\slowQueriesEmptyState,
  eindexGlobal*).
• Added Section 10: Error handling documenting the status-code mapping from \LibSQLTransportError\ to \DatabaseConfigError, \AuthenticationError\ (for 400/401/403), \ConnectionError\ (status 0), and \QueryError.
• Renumbered Section 11: Testing.
• Added Section 12: Usage examples with TypeScript code examples for connecting via Turso Cloud connection string or local \sqld, running parameterised queries, introspecting schema objects, and executing maintenance integrity checks.
• Renumbered Section 13: Known limitations & future work and Section 14: References accordingly.

Testing

• I have tested this locally
• All existing unit and integration tests pass (\�un test tests/unit/db/libsql tests/integration/db/libsql-provider.test.ts\ — 190 pass)
• Formatted with biome forma

Test Environment

• OS: Windows 11
• Node.js/Bun Version: Bun 1.3.11

Checklist

• My code follows the project's code style guidelines
• I have performed a self-review of my code
• I have updated the documentation accordingly
• New and existing unit tests pass locally with my changes

[cevheri]

Approving this. I checked every claim in the new sections against the provider source rather than reading them for shape, and they hold: the capability table matches getCapabilities() down to explainFormat and the two allowlisted maintenance operations, the four label overrides are quoted exactly, and the error table matches mapLibSQLError() including the 400/401/403 set and the status 0 branch that carries host and port. The usage examples use real signatures, and describeObjects() really does answer { details }.

Section numbering now lands where #862 asked, on mongodb.md's shape, and nothing links to the anchors that moved, so the renumbering is safe.

One trivial note, no change needed: bun run format runs biome, which does not touch markdown, so that checkbox is a no-op for this file.

Worth saying plainly: this is your third PR here and the first to land, after #935 was closed on assignment grounds and #945 stood down for this one. Thank you for staying with it, and for picking the doc up at the standard rather than at the minimum.
See you next PR 👍