fix(ai): seed React types for tsx linting so JSX resolves

A tsx script linted with `<div>` reported three false positives —
"JSX.IntrinsicElements does not exist" and "React not in scope" —
because type acquisition only ran for bun/bunnative, so @types/react
never loaded. The editor had the same gap: it creates an ATA instance
for tsx but never seeds react.

Add a shared ataSeedImport(scriptLang) (bun -> bun-types, tsx -> react)
that both the editor and the headless linter seed through, and extend
the headless trigger to tsx. Parity by construction: neither path can
seed differently. jsx routes through the lenient JavaScript worker,
which does not flag JSX, so it needs no seed.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

frontend/src/lib/components/Editor.svelte

@@ -105,7 +105,7 @@
 		ensureResourceTypeNamespace,
 		fetchCustomWmillTypesData
 	} from './lint/typescriptExtraLibs'
-	import { createWindmillAta, genAtaRoot } from './lint/typescriptAta'
+	import { ataSeedImport, createWindmillAta, genAtaRoot } from './lint/typescriptAta'
 	import { readModelMarkers } from './lint/markers'
 	import { registerEditor as registerLintEditor } from './lint/headlessModelHost'
 	import { buildDenoImportMap, hasLanguageServers, lspServersFor } from './lint/lspLanguageConfig'
@@ -1625,10 +1625,11 @@
 					}
 				}
 			})
-			if (scriptLang == 'bun') {
-				ata?.('import "bun-types"')
+			const seed = ataSeedImport(scriptLang)
+			if (seed) {
+				ata?.(seed)
 			}
-			if (scriptLang == 'bunnative' || scriptLang == 'bun') {
+			if (scriptLang == 'bunnative' || scriptLang == 'bun' || scriptLang == 'tsx') {
 				ata?.(code ?? '')
 			}
 			dispatch('ataReady')

frontend/src/lib/components/lint/headlessLint.ts

@@ -20,7 +20,7 @@ import {
 	releaseOwnedModel
 } from './headlessModelHost'
 import { ensureCustomWmillTypes, ensureResourceTypeNamespace } from './typescriptExtraLibs'
-import { createWindmillAta, genAtaRoot } from './typescriptAta'
+import { ataSeedImport, createWindmillAta, genAtaRoot } from './typescriptAta'
 import { lintWithLsp } from './headlessLsp'
 
 // Lints code without a mounted editor, by driving the same Monaco model + global
@@ -152,7 +152,7 @@ async function lintOne(
 			)
 		}
 
-		if (req.scriptLang === 'bun' || req.scriptLang === 'bunnative') {
+		if (req.scriptLang === 'bun' || req.scriptLang === 'bunnative' || req.scriptLang === 'tsx') {
 			await withDeadline(
 				acquireTypes(req, ownedUri).catch((e) =>
 					console.error('headlessLint: type acquisition failed', e)
@@ -189,9 +189,8 @@ async function acquireTypes(req: HeadlessLintRequest, uriString: string): Promis
 			absolutePathExtraLibs
 		})
 		ataByKey.set(key, ata)
-		if (req.scriptLang === 'bun') {
-			await ata('import "bun-types"')
-		}
+		const seed = ataSeedImport(req.scriptLang)
+		if (seed) await ata(seed)
 	}
 	await ata(req.content)
 }

frontend/src/lib/components/lint/typescriptAta.ts

@@ -13,6 +13,18 @@ import { lspTokenStore } from '$lib/stores'
 // global typescriptDefaults. Without it, TypeScript reports every third-party import
 // as unresolved, so headless linting and the editor must acquire types the same way.
 
+/**
+ * The import a language must feed to ATA so its ambient types resolve, even when the code
+ * itself does not import them: `bun-types` for bun's globals, `react` for tsx's JSX namespace
+ * (without it, `<div>` reports "JSX.IntrinsicElements does not exist" / "React not in scope").
+ * The editor and the headless linter both seed through this so their diagnostics can't drift.
+ */
+export function ataSeedImport(scriptLang: string | undefined): string | undefined {
+	if (scriptLang === 'bun') return 'import "bun-types"'
+	if (scriptLang === 'tsx') return 'import "react"'
+	return undefined
+}
+
 export async function genAtaRoot(workspace: string): Promise<string> {
 	let token = get(lspTokenStore)
 	if (!token) {