feat: widgets and ai chat

apps/api/.env.example

@@ -40,4 +40,16 @@ LICENSE_KEY=""
 
 # SSO (Optional)
 # For enterprise SSO with SAML (future support)
-# SSO_ENCRYPTION_KEY="your-32-character-secret-key"
+# SSO_ENCRYPTION_KEY="your-32-character-secret-key"
+
+# AI Assistant (Optional)
+# Per-provider API keys. The dashboard model picker exposes Gemini 3 Flash
+# (Google) and GPT-4o (OpenAI). Anthropic is supported in code but not in the
+# picker UI. Set at least one key to enable the assistant.
+OPENAI_API_KEY=""
+GOOGLE_API_KEY=""
+ANTHROPIC_API_KEY=""
+
+# Tinybird event tracking for AI observability (optional — silently skipped when not set)
+# TINYBIRD_TOKEN=""
+# TINYBIRD_BASE_URL="https://api.tinybird.co"