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/prompts/generator.py

@@ -22,7 +22,7 @@ from typing import Tuple
 import jinja2
 import json_repair
 import trio
-from api.utils import hash_str2int
+from common.misc_utils import hash_str2int
 from rag.nlp import rag_tokenizer
 from rag.prompts.template import load_prompt
 from rag.settings import TAG_FLD