feat: 1. replace black with ruff for fomatting and sort import (#489)

2. use tavily from`langchain-tavily` rather than the older one from `langchain-community`

Co-authored-by: Willem Jiang <willem.jiang@gmail.com>

pyproject.toml

@@ -34,6 +34,7 @@ dependencies = [
     "langchain-mcp-adapters>=0.0.9",
     "langchain-deepseek>=0.1.3",
     "wikipedia>=1.4.0",
+    "langchain-tavily<0.3",
     "langgraph-checkpoint-mongodb>=0.1.4",
     "langgraph-checkpoint-postgres==2.0.21",
 ]
@@ -41,7 +42,6 @@ dependencies = [
 [project.optional-dependencies]
 dev = [
     "ruff",
-    "black>=24.2.0",
     "langgraph-cli[inmem]>=0.2.10",
 ]
 test = [
@@ -68,12 +68,13 @@ fail_under = 25
 [tool.hatch.build.targets.wheel]
 packages = ["src"]
 
-[tool.black]
+[tool.ruff]
 line-length = 88
-target-version = ["py312"]
-include = '\.pyi?$'
-extend-exclude = '''
-# A regex preceded with ^/ will apply only to files and directories
-# in the root of the project.
-^/build/
-'''
+indent-width = 4
+target-version = "py312"
+extend-include = ["*.pyi"]
+
+[tool.ruff.format]
+indent-style = "space"
+line-ending = "auto"
+exclude = ['^/build/']