update docker file

Dockerfile

@@ -1,33 +1,27 @@
-# → Use official slim Python base
+# Use official slim base
 FROM python:3.12-slim
 
 # Install uv package manager
 COPY --from=ghcr.io/astral-sh/uv:latest /uv /uvx /bin/
 
-# Ensure clean python environment and no stray bytecode
 ENV PYTHONUNBUFFERED=1 \
-    PYTHONDONTWRITEBYTECODE=1
+    PYTHONDONTWRITEBYTECODE=1 \
+    UV_CACHE_DIR=/app/.uv_cache
 
-# Set working directory inside container
+# Set working directory
 WORKDIR /app
 
-# Copy lock and project config first for layer caching
+# Create writable cache directory
+RUN mkdir -p /app/.uv_cache
+
+# Copy pyproject files
 COPY pyproject.toml uv.lock ./.python-version /app/
 
-# Install dependencies only (not installing the app code yet)
-RUN --mount=type=cache,target=/root/.cache/uv \
-    uv sync --frozen --no-install-project
+# Install dependencies
+RUN uv sync --frozen --no-install-project
 
-# Copy the full app source code
+# Copy app source
 COPY . /app
 
-# Install app code on top of deps (no dev dependencies)
-RUN --mount=type=cache,target=/root/.cache/uv \
-    uv sync --frozen --no-dev
-
-# Expose port
-ENV PORT=8000
-EXPOSE $PORT
-
 # Start FastAPI with uvicorn via uv-managed venv
 CMD ["uv", "run", "uvicorn", "main:app", "--host", "0.0.0.0", "--port", "8000"]