Update Docker file and add more descriptive comments

Dockerfile

@@ -1,24 +1,41 @@
-# Use the official Python 3.11 slim image as the base image
+# Use the official lightweight Python 3.11 slim image as the base
 FROM python:3.11-slim
 
-# Install curl (if not already present) and install uv using its standalone installer
-RUN apt-get update && apt-get install -y curl && \
+# Install uv using its standalone installer
+#   - `apt-get update` fetches the latest package lists
+#   - `apt-get install -y --no-install-recommends curl` installs curl to fetch the uv installer
+#   - `curl -LsSf` downloads and runs the uv installer script
+#   - `apt-get remove -y curl` removes curl after installation to save space
+#   - `apt-get clean && rm -rf /var/lib/apt/lists/*` removes cached package lists to reduce image size
+RUN apt-get update && apt-get install -y --no-install-recommends curl && \
     curl -LsSf https://astral.sh/uv/install.sh | sh && \
-    rm -rf /var/lib/apt/lists/*
+    apt-get remove -y curl && \
+    apt-get clean && rm -rf /var/lib/apt/lists/*
+
+# Add uv to the system PATH so it can be run globally
+ENV PATH="/root/.local/bin:$PATH"
 
 # Set the working directory in the container
 WORKDIR /app
 
-# Copy all project files into the container
-COPY . .
+# Copy dependency files first (pyproject.toml & uv.lock) to leverage Docker’s build cache
+#   - Ensures that if only the application code changes, dependencies do not need to be reinstalled
+COPY pyproject.toml uv.lock /app/
 
-# Pre-sync the project’s virtual environment and install dependencies
-# This command reads your pyproject.toml (and uv.lock if available) and creates a .venv with all required packages.
-RUN /root/.local/bin/uv sync
+# Install dependencies using uv
+#   - Reads pyproject.toml (and uv.lock, if available) to install dependencies
+#   - Creates a .venv in the project directory with all required packages
+RUN uv sync
+
+# Copy the remaining project files into the container
+COPY . .
 
-# Gradio port 7860
+# Document the port used by Gradio (optional)
+#   - This does not actually expose the port, it is just metadata for users
+#   - To actually expose the port, use `docker run -p 7860:7860 <image>`
 EXPOSE 7860
 
-# Define the command to run your application using uv.
-# uv run will automatically ensure that the built-in venv is active and dependencies are up to date.
-CMD ["/root/.local/bin/uv", "run", "python", "-m", "src.app"]
+# Define the command to start the application
+#   - `uv run` ensures that the virtual environment is activated and dependencies are up to date
+#   - `python -m src.app` runs the main application module
+CMD ["uv", "run", "python", "-m", "src.app"]