Feat: repair corrupted PDF files on upload automatically (#7693)

### What problem does this PR solve?

Try the best to repair corrupted PDF files on upload automatically.

### Type of change

- [x] New Feature (non-breaking change which adds functionality)

Dockerfile

@@ -59,7 +59,8 @@ RUN --mount=type=cache,id=ragflow_apt,target=/var/cache/apt,sharing=locked \
     apt install -y libatk-bridge2.0-0 && \
     apt install -y libpython3-dev libgtk-4-1 libnss3 xdg-utils libgbm-dev && \
     apt install -y libjemalloc-dev && \
-    apt install -y python3-pip pipx nginx unzip curl wget git vim less
+    apt install -y python3-pip pipx nginx unzip curl wget git vim less && \
+    apt install -y ghostscript
 
 RUN if [ "$NEED_MIRROR" == "1" ]; then \
         pip3 config set global.index-url https://mirrors.aliyun.com/pypi/simple && \