🔍 Add description, readme and urls to pyproject.toml metadata (#87)

Extra metadata to go on the PyPI site. Thought some of this was auto-populated from Cargo.toml via maturin, but maybe not anymore. Xref https://packaging.python.org/en/latest/specifications/pyproject-toml/#declaring-project-metadata-the-project-table

Author: weiji14

pyproject.toml

@@ -1,5 +1,7 @@
 [project]
 name = "cog3pio"
+description = "Cloud-optimized GeoTIFF ... Parallel I/O"
+readme = "README.md"
 requires-python = ">=3.13"
 license = "MIT OR Apache-2.0"
 license-files = ["LICENSE-APACHE", "LICENSE-MIT"]
@@ -25,6 +27,11 @@ dependencies = [
 ]
 dynamic = ["version"]
 
+[project.urls]
+"Changelog" = "https://cog3pio.readthedocs.io/en/latest/changelog"
+"Documentation" = "https://cog3pio.readthedocs.io"
+"Source Code" = "https://github.com/weiji14/cog3pio"
+
 [project.entry-points."xarray.backends"]
 cog3pio = "cog3pio.xarray_backend:Cog3pioBackendEntrypoint"