Self-host LanguageTool in Docker Compose

- Add erikvl87/languagetool service on the internal network
  (port 8010, English only by default — change langsToLoad to add more)
- 256 MB min / 512 MB max heap; healthcheck waits up to ~3 min for
  first startup while Java initialises
- Server LANGUAGETOOL_URL hardwired to http://languagetool:8010/v2 —
  no character limits, no rate limits, fully private
- Remove 40 000-char cap from lint route (not needed self-hosted)
- Bump fetch timeout to 30 s for cold-start requests

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

docker-compose.yml

@@ -11,6 +11,7 @@ services:
       - OLLAMA_URL=${OLLAMA_URL:-https://ai.binarygnome.com}
       - OLLAMA_MODEL=${OLLAMA_MODEL:-gemma4:latest}
       - OLLAMA_API_KEY=${OLLAMA_API_KEY:-}
+      - LANGUAGETOOL_URL=http://languagetool:8010/v2
     extra_hosts:
       - "host-gateway:host-gateway"
     networks:
@@ -22,6 +23,23 @@ services:
       retries: 10
       start_period: 15s
 
+  languagetool:
+    image: erikvl87/languagetool
+    restart: unless-stopped
+    environment:
+      - Java_Xms=256m
+      - Java_Xmx=512m
+      # Add more languages (comma-separated) or remove this line to load all
+      - langsToLoad=en
+    networks:
+      - internal
+    healthcheck:
+      test: ["CMD-SHELL", "wget -qO- http://localhost:8010/v2/languages > /dev/null"]
+      interval: 10s
+      timeout: 5s
+      retries: 18        # LT takes ~30–60 s to start on first run
+      start_period: 90s
+
   app:
     build: ./frontend
     restart: unless-stopped

server/routes/lint.js

@@ -11,7 +11,6 @@ router.use(auth)
 router.post('/check', async (req, res) => {
   const { text, language = 'en-US' } = req.body || {}
   if (!text || typeof text !== 'string') return res.status(400).json({ error: 'text required' })
-  if (text.length > 40000) return res.status(400).json({ error: 'text too long (max 40 000 chars)' })
 
   try {
     const body = new URLSearchParams({
@@ -25,7 +24,7 @@ router.post('/check', async (req, res) => {
       method:  'POST',
       headers: { 'Content-Type': 'application/x-www-form-urlencoded', Accept: 'application/json' },
       body:    body.toString(),
-      signal:  AbortSignal.timeout(20000),
+      signal:  AbortSignal.timeout(30000),
     })
 
     if (!r.ok) {