feat(dataroom): bilingual descriptions, drag-drop multi-file upload, edit existing upload descriptions

- lib/translate.ts: LiteLLM DE<>EN translation utility
- Migration 006: description_de/description_en on both dataroom tables
- Admin + investor upload APIs: accept description+lang, auto-translate the other language on save
- PATCH /api/admin/dataroom/documents/[id]: description path in addition to display_name path
- PATCH /api/dataroom/uploads/[id]: investor can edit their own upload descriptions
- PATCH /api/admin/dataroom/investors/[id]/uploads: admin can edit investor upload descriptions
- All GET queries updated to return description fields
- Admin dataroom: drop zone replaces upload button, multi-file, inline description editor per doc and per investor upload
- Investor dataroom: drop zone, multi-file, description+lang textarea before upload, inline description editing on existing uploads

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

pitch-deck/lib/translate.ts

@@ -0,0 +1,28 @@
+const LITELLM_URL = process.env.LITELLM_URL || 'https://llm-dev.meghsakha.com'
+const LITELLM_MODEL = process.env.LITELLM_MODEL || 'gpt-oss-120b'
+const LITELLM_API_KEY = process.env.LITELLM_API_KEY || ''
+
+export async function translateText(text: string, from: 'de' | 'en'): Promise<string | null> {
+  if (!text.trim()) return null
+  const toLang = from === 'de' ? 'English' : 'German'
+  try {
+    const r = await fetch(`${LITELLM_URL}/chat/completions`, {
+      method: 'POST',
+      headers: { 'Content-Type': 'application/json', 'Authorization': `Bearer ${LITELLM_API_KEY}` },
+      body: JSON.stringify({
+        model: LITELLM_MODEL,
+        messages: [
+          { role: 'system', content: `Translate the following text to ${toLang}. Output only the translated text, nothing else.` },
+          { role: 'user', content: text },
+        ],
+        max_tokens: 1000,
+        temperature: 0.1,
+      }),
+    })
+    if (!r.ok) return null
+    const data = await r.json()
+    return (data.choices?.[0]?.message?.content as string | undefined)?.trim() || null
+  } catch {
+    return null
+  }
+}