Add __version__ identifier

- `lalib.__version__` is dynamically assigned
- the format is "x.y.z[.dev0|aN|bN|rcN|.postM]"
  where x, y, z, M, and N are non-negative integers
  + x, y, and z model the "major", "minor", and "patch"
    parts of semantic versioning
    (See: https://semver.org/#semantic-versioning-200)
  + M is a single digit and N either 1 or 2
  => This complies with (a strict subset of) PEP440
- add unit tests for the `__version__` identifier

poetry.lock

@@ -936,6 +936,17 @@ files = [
     {file = "ruff-0.6.4.tar.gz", hash = "sha256:ac3b5bfbee99973f80aa1b7cbd1c9cbce200883bdd067300c22a6cc1c7fba212"},
 ]
 
+[[package]]
+name = "semver"
+version = "3.0.2"
+description = "Python helper for Semantic Versioning (https://semver.org)"
+optional = false
+python-versions = ">=3.7"
+files = [
+    {file = "semver-3.0.2-py3-none-any.whl", hash = "sha256:b1ea4686fe70b981f85359eda33199d60c53964284e0cfb4977d243e37cf4bf4"},
+    {file = "semver-3.0.2.tar.gz", hash = "sha256:6253adb39c70f6e51afed2fa7152bcd414c411286088fb4b9effb133885ab4cc"},
+]
+
 [[package]]
 name = "setuptools"
 version = "74.1.2"
@@ -1006,4 +1017,4 @@ files = [
 [metadata]
 lock-version = "2.0"
 python-versions = "^3.9"
-content-hash = "d57341979796164059f8d01fd2cc367cc21f1000a91b7d96fb02c6319a9b012b"
+content-hash = "4ba46548b380fe7c34cf4ed48492253b2d3a1866f86c8d8bf569eb18829281c2"