feat: Add presence heartbeat for Matrix online status

- matrix-gateway: POST /internal/matrix/presence/online endpoint
- usePresenceHeartbeat hook with activity tracking
- Auto away after 5 min inactivity
- Offline on page close/visibility change
- Integrated in MatrixChatRoom component

services/ocr-service/Dockerfile

@@ -0,0 +1,31 @@
+FROM python:3.11-slim
+
+# Встановити системні залежності
+RUN apt-get update && apt-get install -y \
+    tesseract-ocr \
+    tesseract-ocr-ukr \
+    tesseract-ocr-eng \
+    tesseract-ocr-rus \
+    libtesseract-dev \
+    libgl1 \
+    libglib2.0-0 \
+    && rm -rf /var/lib/apt/lists/*
+
+WORKDIR /app
+
+# Копіювати requirements
+COPY requirements.txt .
+
+# Встановити Python залежності
+RUN pip install --no-cache-dir -r requirements.txt
+
+# Завантажити EasyOCR моделі
+RUN python -c "import easyocr; easyocr.Reader(['uk', 'en'], gpu=False)"
+
+# Копіювати код
+COPY app/ ./app/
+
+EXPOSE 8896
+
+CMD ["uvicorn", "app.main:app", "--host", "0.0.0.0", "--port", "8896"]
+