chore: migrate from tool.uv.dev-dependencies to dependency-groups.dev

Replace deprecated `tool.uv.dev-dependencies` with the new
`dependency-groups.dev` format as recommended by uv. This ensures
forward compatibility and removes the deprecation warning.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <noreply@anthropic.com>

Author: JacobCoffee

pyproject.toml

@@ -75,8 +75,8 @@ members = [
     "services/bot",
 ]
 
-[tool.uv]
-dev-dependencies = [
+[dependency-groups]
+dev = [
     # - Testing
     "pytest>=7.4.3",
     "coverage>=7.3.2",