feat(infra): add Ollama env vars to .env.example (#737)

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

.env.example

@@ -72,6 +72,25 @@ VITE_SENTRY_DSN=
 # Sentry/GlitchTip auth token for source map upload at build time (optional)
 SENTRY_AUTH_TOKEN=
 
+# NL search — Ollama LLM inference
+# Leave APP_OLLAMA_BASE_URL empty to disable NL search (safe default for CX32 / CI).
+# Set to http://ollama:11434 to enable. Requires CX42 (16 GB RAM) to run alongside OCR.
+APP_OLLAMA_BASE_URL=http://ollama:11434
+
+# CPU limit: 4.0 is safe on both CX32 (4 vCPUs) and CX42 (8 vCPUs).
+# Raise to 7.5 on CX42 for full throughput.
+OLLAMA_CPU_LIMIT=4.0
+
+# Memory limit: requires CX42 (16 GB) to run alongside OCR.
+# Reduce or set APP_OLLAMA_BASE_URL= on smaller hosts.
+OLLAMA_MEM_LIMIT=8g
+
+# Ollama API key — set on the Ollama service to restrict inference API access on archiv-net.
+# Generate with: openssl rand -hex 32
+# NOTE: Empirically verified that OLLAMA_API_KEY is NOT enforced in Ollama 0.6.5 (ADR-028 §7).
+# Retained for forward compatibility. Leave empty for unauthenticated access.
+OLLAMA_API_KEY=
+
 # Production SMTP — uncomment and fill in to send real emails instead of catching them
 # APP_BASE_URL=https://your-domain.example.com
 # MAIL_HOST=smtp.example.com