Update Dockerfile

Dockerfile

@@ -1,14 +1,14 @@
 FROM python:3.9-slim
 
-# 1. Install system dependencies
-# We need Postgres, MariaDB (MySQL), and build tools for python libraries
+# 1. Install Database Servers and CLIs
+# We install sqlite3, postgresql-client, and mariadb-client
+# Reordered slightly to ensure Docker rebuilds this layer and installs sqlite3
 RUN apt-get update && apt-get install -y \
+    sqlite3 \
     postgresql \
-    postgresql-contrib \
+    postgresql-client \
     mariadb-server \
-    libpq-dev \
-    gcc \
-    python3-dev \
+    mariadb-client \
     && rm -rf /var/lib/apt/lists/*
 
 # 2. Set up Python environment
@@ -21,9 +21,7 @@ COPY app.py .
 COPY start.sh .
 RUN chmod +x start.sh
 
-# 4. Permissions: 
-# Postgres and MySQL don't like running as root.
-# We will fix ownership so we can start them smoothly in the start script.
+# 4. Fix Permissions for DB startup
 RUN mkdir -p /var/run/mysqld && \
     chown -R postgres:postgres /var/lib/postgresql && \
     chown -R mysql:mysql /var/lib/mysql && \