feat: add project infrastructure

- Add src/ structure with config and logger modules
- Add .env.example with required environment variables
- Add python-dotenv dependency
- Add TASK.md with implementation roadmap

uv.lock

@@ -33,11 +33,15 @@ name = "dataset-tg-bot"
 version = "0.1.0"
 source = { virtual = "." }
 dependencies = [
+    { name = "python-dotenv" },
     { name = "python-telegram-bot" },
 ]
 
 [package.metadata]
-requires-dist = [{ name = "python-telegram-bot", specifier = ">=22.6" }]
+requires-dist = [
+    { name = "python-dotenv", specifier = ">=1.2.1" },
+    { name = "python-telegram-bot", specifier = ">=22.6" },
+]
 
 [[package]]
 name = "h11"
@@ -85,6 +89,15 @@ wheels = [
     { url = "https://files.pythonhosted.org/packages/0e/61/66938bbb5fc52dbdf84594873d5b51fb1f7c7794e9c0f5bd885f30bc507b/idna-3.11-py3-none-any.whl", hash = "sha256:771a87f49d9defaf64091e6e6fe9c18d4833f140bd19464795bc32d966ca37ea", size = 71008, upload-time = "2025-10-12T14:55:18.883Z" },
 ]
 
+[[package]]
+name = "python-dotenv"
+version = "1.2.1"
+source = { registry = "https://pypi.org/simple" }
+sdist = { url = "https://files.pythonhosted.org/packages/f0/26/19cadc79a718c5edbec86fd4919a6b6d3f681039a2f6d66d14be94e75fb9/python_dotenv-1.2.1.tar.gz", hash = "sha256:42667e897e16ab0d66954af0e60a9caa94f0fd4ecf3aaf6d2d260eec1aa36ad6", size = 44221, upload-time = "2025-10-26T15:12:10.434Z" }
+wheels = [
+    { url = "https://files.pythonhosted.org/packages/14/1b/a298b06749107c305e1fe0f814c6c74aea7b2f1e10989cb30f544a1b3253/python_dotenv-1.2.1-py3-none-any.whl", hash = "sha256:b81ee9561e9ca4004139c6cbba3a238c32b03e4894671e181b671e8cb8425d61", size = 21230, upload-time = "2025-10-26T15:12:09.109Z" },
+]
+
 [[package]]
 name = "python-telegram-bot"
 version = "22.6"