## Summary
Step 2 of the SQL Editor testability plan.
`SQLEditorContext` already wrapped the Monaco refs and exposed a few
semantic imperative helpers (`getEditorSql`, `clearHighlights`,
`applyErrorHighlight`, `refocusEditor`, …). This finishes that
abstraction so no hook or controller touches
`editorRef.current`/`diffEditorRef.current` directly anymore — they only
call the port. The port is what will let Step 3's test harness inject a
real in-memory editor adapter instead of mocking Monaco; production
wires it to the real Monaco refs, unchanged.
- Extends the context value with two semantic controllers, backed by the
existing refs:
- `editor: EditorController` — `isReady`, `getValue`,
`getSelectionStartLine`, `getSql` (today's `getEditorSql`), `replaceAll`
(wraps the repeated `executeEdits(...)` pattern), `focus`,
`revealLineInCenter`, `highlightErrorLine` (today's
`applyErrorHighlight`), `clearHighlights`.
- `diff: DiffController` — `isMounted`, `getModifiedValue`, `setDiff`
(the diff-sync effect body), `attach` (today's `handleDiffEditorMount`).
- Migrates every touch point off raw refs onto the port:
`useSqlEditorExecution`, `usePrettifyQuery`, `useSqlEditorShortcuts`,
`SQLEditorControllers`' `readEditorSql`, and `useSqlEditorAi`'s
`acceptAiHandler`/`drainDiffRequest`/`handleDiffEditorMount`/diff-sync
effect.
- `SQLEditorEditorPanel.tsx` is intentionally left untouched — it wires
the raw refs into the real Monaco/DiffEditor React components for
rendering, which isn't decision logic to abstract.
Behavior-preserving.
## Test plan
- [x] `pnpm --filter studio typecheck`
- [x] `pnpm test:studio -- SQLEditor` (265 tests passing)
- [x] `pnpm --filter studio run lint:ratchet`
## Summary
Continues the SQLEditor decomposition. Pulls four cohesive concerns out
of the `SQLEditorContent` composition root into co-located `use*` hooks.
## New hooks
- `useSnippetIdentity` — derives `id` / `generatedNewSnippetName` /
`isLoading` from the URL + snippet store (keeps the `[urlId]` memo dep
verbatim).
- `useEditorMount` — the editor `onMount` (scroll restore/track) + the
mount counter that lets a pre-mount diff request re-run.
- `usePrettifyQuery` — formats the editor SQL in place and writes it
back to the store.
- `useSnippetTitleGenerator` — the title-generation mutation +
`setAiTitle`.
Charis