Refa: http API create dataset and test cases (#7393)

### What problem does this PR solve?

This PR introduces Pydantic-based validation for the create dataset HTTP
API, improving code clarity and robustness. Key changes include:
1. Pydantic Validation
2. ​​Error Handling
3. Test Updates
4. Documentation

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)
- [x] Documentation Update
- [x] Refactoring

sdk/python/pyproject.toml

@@ -2,31 +2,26 @@
 name = "ragflow-sdk"
 version = "0.18.0"
 description = "Python client sdk of [RAGFlow](https://github.com/infiniflow/ragflow). RAGFlow is an open-source RAG (Retrieval-Augmented Generation) engine based on deep document understanding."
-authors = [
-    { name = "Zhichang Yu", email = "yuzhichang@gmail.com" }
-]
+authors = [{ name = "Zhichang Yu", email = "yuzhichang@gmail.com" }]
 license = { text = "Apache License, Version 2.0" }
 readme = "README.md"
 requires-python = ">=3.10,<3.13"
-dependencies = [
-    "requests>=2.30.0,<3.0.0",
-    "beartype>=0.18.5,<0.19.0",
-    "pytest>=8.0.0,<9.0.0",
-    "requests-toolbelt>=1.0.0",
-    "python-docx>=1.1.2",
+dependencies = ["requests>=2.30.0,<3.0.0", "beartype>=0.18.5,<0.19.0"]
+
+
+[dependency-groups]
+test = [
+    "hypothesis>=6.131.9",
     "openpyxl>=3.1.5",
-    "python-pptx>=1.0.2",
     "pillow>=11.1.0",
+    "pytest>=8.3.5",
+    "python-docx>=1.1.2",
+    "python-pptx>=1.0.2",
     "reportlab>=4.3.1",
+    "requests>=2.32.3",
+    "requests-toolbelt>=1.0.0",
 ]
 
-[project.optional-dependencies]
-test = [
-    "pytest>=8.0.0,<9.0.0"
-]
 
 [tool.pytest.ini_options]
-markers = [
-    "slow: marks tests as slow (deselect with '-m \"not slow\"')",
-    "wip: marks tests as work in progress (deselect with '-m \"not wip\"')"
-]
+markers = ["slow: marks tests as slow (deselect with '-m \"not slow\"')"]