chore: revert "build: remove uv dynamic versioning (#824)" (#827)

Turns out it creates more problems than solves and requires more
intervention into release-please to also update `uv.lock`.

release-please still uses SemVer values in its PRs, but they are
normalized during build (see
[here](https://packaging.python.org/en/latest/specifications/version-specifiers/#normalization)).

Author: ishymko

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "a2a-sdk"
-version = "0.3.25"
+dynamic = ["version"]
 description = "A2A Python SDK"
 readme = "README.md"
 license = "Apache-2.0"
@@ -62,7 +62,7 @@ changelog = "https://github.com/a2aproject/a2a-python/blob/main/CHANGELOG.md"
 documentation = "https://a2a-protocol.org/latest/sdk/python/"
 
 [build-system]
-requires = ["hatchling", "hatch-build-scripts"]
+requires = ["hatchling", "uv-dynamic-versioning", "hatch-build-scripts"]
 build-backend = "hatchling.build"
 
 [tool.hatch.build.hooks.build-scripts]
@@ -72,6 +72,8 @@ artifacts = ["src/a2a/types/a2a.json"]
 commands = ["bash scripts/gen_proto.sh"]
 work_dir = "."
 
+[tool.hatch.version]
+source = "uv-dynamic-versioning"
 
 [tool.hatch.build.targets.wheel]
 packages = ["src/a2a"]
@@ -102,6 +104,9 @@ filterwarnings = [
 [tool.pytest-asyncio]
 mode = "strict"
 
+[tool.uv-dynamic-versioning]
+vcs = "git"
+style = "pep440"
 
 [dependency-groups]
 dev = [
@@ -114,6 +119,7 @@ dev = [
   "pytest-xdist>=3.6.1",
   "respx>=0.20.2",
   "ruff>=0.12.8",
+  "uv-dynamic-versioning>=0.8.2",
   "types-protobuf",
   "types-requests",
   "pre-commit",