chore(ts7): adopt the TypeScript 7 native compiler (tsgo)

Make the editor packages compatible with, and benefit from, the native Go
compiler (TypeScript 7 / tsgo) while keeping the npm publish path on stable tsc.

- Add @typescript/native-preview (pinned 7.0.0-dev.20260624.1). tsgo coexists
  with typescript@6, which Next typegen and the IDE plugin still need until the
  TS 7.1 programmatic API ships.
- Fix two react-three-fiber JSX augmentations the native checker rejects but
  tsc tolerated:
  - viewer: map only LineBasicNodeMaterial (the one webgpu node material used as
    a JSX tag) instead of the whole three/webgpu namespace (TS2320/TS2590).
  - plane-box-select-tool: drop the redundant `IntrinsicElements extends
    ThreeElements` block — it duplicated R3F's global augmentation and, by
    referencing @react-three/fiber's ThreeElements directly, hit a bun peer-dep
    variant-directory duplicate under tsgo (TS2320). r3f.d.ts already covers
    those JSX intrinsics. Types-only — no runtime change.
- check-types -> tsgo --noEmit (editor, @repo/ui, editor app, ifc-converter app)
- emit-package dev watch -> tsgo --build --watch
- build/publish stay tsc --build (prepublishOnly + release.yml unchanged;
  emitted .d.ts is byte-identical to tsc output)
- bump next 16.2.6 -> 16.2.9

tsc remains the source of truth and fallback. Published artifacts unchanged.

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

packages/editor/package.json

@@ -8,7 +8,7 @@
     "./catalog": "./src/components/ui/item-catalog/catalog-items.tsx"
   },
   "scripts": {
-    "check-types": "tsc --noEmit"
+    "check-types": "tsgo --noEmit"
   },
   "peerDependencies": {
     "@pascal-app/core": "^0.9.1",

packages/editor/src/components/tools/select/plane-box-select-tool.tsx

@@ -10,7 +10,6 @@ import {
   type ZoneNode,
 } from '@pascal-app/core'
 import { useViewer } from '@pascal-app/viewer'
-import type { ThreeElements } from '@react-three/fiber'
 import { useThree } from '@react-three/fiber'
 import { useCallback, useEffect, useRef } from 'react'
 import {
@@ -34,12 +33,6 @@ import { CursorSphere } from '../shared/cursor-sphere'
 import { isBoxSelectPointerSuppressed, markBoxSelectHandled } from './box-select-state'
 import { collectSelectableCandidateIds } from './select-candidates'
 
-declare module 'react/jsx-runtime' {
-  namespace JSX {
-    interface IntrinsicElements extends ThreeElements {}
-  }
-}
-
 type Bounds = { minX: number; maxX: number; minZ: number; maxZ: number }
 
 const BOX_SELECT_ACCENT_COLOR = '#818cf8'