chore: clean up repo for public release

- Remove BMAD framework, IDE configs, dev screenshots, test files,
  internal docs, and backup files
- Rename keep-notes/ to memento-note/
- Update all references from keep-notes to memento-note
- Add Apache 2.0 license with Commons Clause (non-commercial restriction)
- Add clean .gitignore and .env.docker.example

memento-note/app/api/ai/translate/route.ts

@@ -0,0 +1,30 @@
+import { NextRequest, NextResponse } from 'next/server'
+import { auth } from '@/auth'
+import { getTagsProvider } from '@/lib/ai/factory'
+import { getSystemConfig } from '@/lib/config'
+
+export async function POST(request: NextRequest) {
+  try {
+    const session = await auth()
+    if (!session?.user?.id) {
+      return NextResponse.json({ error: 'Unauthorized' }, { status: 401 })
+    }
+
+    const { text, targetLanguage } = await request.json()
+
+    if (!text || !targetLanguage) {
+      return NextResponse.json({ error: 'text and targetLanguage are required' }, { status: 400 })
+    }
+
+    const config = await getSystemConfig()
+    const provider = getTagsProvider(config)
+
+    const prompt = `Translate the following text to ${targetLanguage}. Return ONLY the translated text, no explanation, no preamble, no quotes:\n\n${text}`
+
+    const translatedText = await provider.generateText(prompt)
+
+    return NextResponse.json({ translatedText: translatedText.trim() })
+  } catch (error: any) {
+    return NextResponse.json({ error: error.message || 'Translation failed' }, { status: 500 })
+  }
+}