feat: remove visual query builder

[EVWorth]

Summary

Removes the Visual Query Builder (a.k.a. QueryBuilder) feature — the drag-table visual SQL builder that opened via toolbar/titlebar/menu and generated SQL against the live MySQL connection.

Also brings lefthook closer to parity with CI by adding 3 missing fast checks (lint, type-check, clippy).

Why

User-requested removal. Feature was frontend-only (no new dependencies), so drop cost is low. Lefthook additions catch CI-failing issues before push instead of after.

Changes

Removal (22 files, +5/-3742)

Area	Files	Action
Component	src/components/querybuilder/QueryBuilder.tsx	Delete (1076 lines)
Engine	src/lib/query-builder-engine.ts + test (464 lines)	Delete
Component tests	2 test files (1756 lines, 40 PNG screenshots)	Delete
Type	src/types/index.ts	Remove "querybuilder" from EditorTab.type
Store	src/stores/editorStore.ts	Remove addQueryBuilderTab action
Panel routing	src/components/layout/MainPanel.tsx	Remove import + branch
Entry points	Toolbar.tsx, TitleBar.tsx, MenuBar.tsx, AppLayout.tsx	Remove button/handler/menu item
Layout test cleanup	4 layout test files + editorStore.test.ts	Remove mocks/assertions
Native menu	src-tauri/src/menu.rs	Remove macOS menu item
Docs	README.md	Remove project-tree entry

Lefthook addition (1 file, +10)

lefthook.yml adds 3 commands that mirror CI's lint-ts and lint-rust jobs, gated by file globs so docs-only commits stay fast:

• lint → npm run lint on *.{ts,tsx,js,jsx}
• type-check → npm run type-check on *.{ts,tsx}
• cargo-clippy → cargo clippy --all-targets --all-features -- -D warnings on *.rs (root: src-tauri/)

Dependencies

Zero new. No changes to package.json, Cargo.toml, tauri.conf.json, or capabilities. The visual builder reused existing getTables/getColumns/executeQuery IPC; lefthook additions don't pull any deps.

Testing

Gate	Result
npm run type-check	Pass (0 errors)
npm run lint	Pass (0 errors; 173 pre-existing warnings)
cargo fmt --all	Clean
cargo clippy --all-targets --all-features -- -D warnings	Clean
npx vitest run	77 files / 1444 tests passing
npx dprint check	Clean
Lefthook pre-commit (new commands)	Pass

Commits

1. chore: format cargo-audit-fix-plan.md (dprint drift) — pre-existing whitespace drift surfaced by dprint
2. feat: remove visual query builder — the actual removal
3. ci: add lint, type-check, clippy to pre-commit — close lefthook ↔ CI gap

Notes

• No Rust/Tauri command changes — feature was purely frontend.
• No design doc to update (no ADR was filed for this feature).
• Rust integration tests, audits, dep-age gate, E2E remain CI-only (require infra).