Strip api.neuronetz.ai from documentation; chat config stays in env

The Ollama URL was leaking via:
  - prose in /en/, /de/, /ja/, /es/, /fr/ docs (oracle, deployment,
    local-testing, ai/module/{overview,embed,training})
  - code blocks teaching users to curl the host directly
  - .env.example, Dockerfile, docker-compose.yml defaults
  - providers.mjs, translate-docs.mjs, build-oracle-index.mjs defaults
  - LandingScripts.astro comment
  - lora-runbook.md prose + SSH host
  - the GET handler at /api/oracle which echoed `ollamaUrl` back to public callers
  - the "Oracle is silent" fallback message at /api/oracle POST

Replacements:
  - prose: "neuronetz.ai" → "your Ollama instance"
  - example URLs in code blocks: https://api.neuronetz.ai → https://your-ollama-host.example
  - code-level defaults: → http://localhost:11434 (Ollama's standard local port)
  - GET /api/oracle: dropped the `ollamaUrl` field; provider + model still exposed
  - runbook SSH host: neuronetz@cloud.neuronetz.ai → <gpu-user>@<gpu-host>

Production chat is unaffected: docs/.env (gitignored) on the production
host still pins OLLAMA_BASE_URL=https://api.neuronetz.ai. The only
change in the running container is that the GET handler no longer
echoes the URL.

analytics.neuronetz.ai (Umami tracking) is intentionally left intact —
it's a public, brand-owned subdomain meant to be visible.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

.gitignore

@@ -46,3 +46,13 @@ docs2/
 # Local-only experiments
 docs.bak/
 *.local
+
+# LoRA corpus build output — regenerated by scripts/build-corpus.mjs.
+# Lives under public/ so Astro serves /corpus/*.jsonl, but is build-time
+# generated and shouldn't enter git.
+docs/public/corpus/
+
+# Research-agent augmentation output — the agent's enriched Q/A pairs.
+# Generated, not curated by hand.
+docs/scripts/extraction/lora-augmentation.jsonl
+docs/scripts/extraction/lora-augmentation.summary.txt