Use dynamic versioning and bump version (#320)

⚠️ Must be merged after #319 and other related PRs.

*Issue #, if available:*

*Description of changes:* Exports `chronos.__version__` and uses it
dynamically in `pyproject.toml`. Bumps version to 2.0.0.


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choice.

pyproject.toml

@@ -1,6 +1,6 @@
 [project]
 name = "chronos-forecasting"
-version = "1.5.3"
+dynamic = ["version"]
 authors = [
   { name = "Abdul Fatir Ansari", email = "ansarnd@amazon.com" },
   { name = "Lorenzo Stella", email = "stellalo@amazon.com" },
@@ -36,6 +36,9 @@ build-backend = "hatchling.build"
 [tool.hatch.build.targets.wheel]
 packages = ["src/chronos"]
 
+[tool.hatch.version]
+path = "src/chronos/__about__.py"
+
 [project.optional-dependencies]
 test = ["pytest~=8.0", "numpy>=1.21,<3", "fev>=0.6.1", "pandas>=2.0,<2.4"]
 typecheck = ["mypy~=1.9"]

src/chronos/__about__.py

@@ -0,0 +1 @@
+__version__ = "2.0.0rc1"

src/chronos/__init__.py

@@ -1,6 +1,7 @@
 # Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
 # SPDX-License-Identifier: Apache-2.0
 
+from .__about__ import __version__
 from .base import BaseChronosPipeline, ForecastType
 from .chronos import (
     ChronosConfig,
@@ -13,6 +14,7 @@ from .chronos2 import Chronos2ForecastingConfig, Chronos2Model, Chronos2Pipeline
 from .chronos_bolt import ChronosBoltConfig, ChronosBoltPipeline
 
 __all__ = [
+    "__version__",
     "BaseChronosPipeline",
     "ForecastType",
     "ChronosConfig",