Added volume definition to dockerfile for session persistence regardless of volume mount status at runtime

Dockerfile

@@ -1,6 +1,8 @@
 FROM oven/bun:latest AS base
 WORKDIR /usr/src/app
+#Persistent session data
 RUN mkdir /sessionData && chmod 777 /sessionData
+VOLUME /sessionData
 # install dependencies into temp directory
 # this will cache them and speed up future builds
 FROM base AS install