fix: Add JSON import assertions for Node.js ESM compatibility (#5507)

Added `with { type: 'json' }` assertions to all JSON imports to ensure compatibility with Node.js ES modules and Playwright environments. This follows the current ESM specification where JSON imports require explicit type assertions.

Affected areas:
- Tailwind config
- i18n locale imports (36 files)
- Test fixtures and spec files
- API client feature flags
- Core color palettes

References:
- https://nodejs.org/api/esm.html
- https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Statements/import/with

🤖 Generated with [Claude Code](https://claude.ai/code)

Co-authored-by: Claude <noreply@anthropic.com>

src/renderer/extensions/vueNodes/components/NodeSlots.spec.ts

@@ -5,7 +5,7 @@ import { type PropType, defineComponent } from 'vue'
 import { createI18n } from 'vue-i18n'
 
 import type { VueNodeData } from '@/composables/graph/useGraphNodeManager'
-import enMessages from '@/locales/en/main.json'
+import enMessages from '@/locales/en/main.json' with { type: 'json' }
 
 import NodeSlots from './NodeSlots.vue'