chore(userbot): optimize Dockerfile with multi-stage build and static ffmpeg

- Multi-stage build: pip deps built in separate stage
- Static ffmpeg binary instead of apt package (avoid 200+ deps)
- Keep only git, mediainfo, wget via apt

userbot/Dockerfile

@@ -1,17 +1,27 @@
+FROM python:3.11-slim AS builder
+
+WORKDIR /src
+COPY requirements.txt .
+RUN pip install --no-cache-dir --user -r requirements.txt
+
 FROM python:3.11-slim
 
-WORKDIR /app
-
 RUN apt-get update && apt-get install -y --no-install-recommends \
-    git wget ffmpeg mediainfo && \ 
-    rm -rf /var/lib/apt/lists/*
+    git \
+    mediainfo \
+    wget \
+    xz-utils \
+    && rm -rf /var/lib/apt/lists/*
 
-COPY requirements.txt /app/
-
-RUN python -m pip install --no-cache-dir --upgrade pip && \
-    python -m pip install --no-cache-dir -r /app/requirements.txt
+RUN wget -qO- https://johnvansickle.com/ffmpeg/releases/ffmpeg-release-amd64-static.tar.xz | \
+    tar xJ && \
+    cp ffmpeg-*-static/ffmpeg /usr/local/bin/ && \
+    cp ffmpeg-*-static/ffprobe /usr/local/bin/ && \
+    rm -rf ffmpeg-*
 
+COPY --from=builder /root/.local /usr/local
 COPY . /app
+WORKDIR /app
 
 ENV PYTHONUNBUFFERED=1