Remove 'get_lan_ip' and add common misc_utils.py (#10880)

### What problem does this PR solve?

Add get_uuid, download_img and hash_str2int into misc_utils.py

### Type of change

- [x] Refactoring

---------

Signed-off-by: Jin Hai <haijin.chn@gmail.com>

rag/flow/splitter/splitter.py

@@ -17,7 +17,7 @@ from functools import partial
 
 import trio
 
-from api.utils import get_uuid
+from common.misc_utils import get_uuid
 from api.utils.base64_image import id2image, image2id
 from deepdoc.parser.pdf_parser import RAGFlowPdfParser
 from rag.flow.base import ProcessBase, ProcessParamBase