Cargo is currently recompiling uv-python on every invocation because the
minified JSON output file is getting a mod time newer than the last run.
Instead, set the mod time of the output file to the same as the input
file.

## Summary

Adds the version for environment variables added in
#16040 and
#16125. as these were in-flight
before documentation versioning was added.

Adds ability to emit a compiler error when added in is missing for
improved reporting to the developer.

e.g. example for the ones fixed in this PR

```shell
error: missing #[attr_added_in("x.y.z")] on `UV_UPLOAD_HTTP_TIMEOUT`
       note: env vars for an upcoming release should be annotated with `#[attr_added_in("next release")]`
   --> crates\uv-static\src\env_vars.rs:593:15
    |
593 |     pub const UV_UPLOAD_HTTP_TIMEOUT: &'static str = "UV_UPLOAD_HTTP_TIMEOUT";
    |               ^^^^^^^^^^^^^^^^^^^^^^

error: missing #[attr_added_in("x.y.z")] on `UV_WORKING_DIRECTORY`
       note: env vars for an upcoming release should be annotated with `#[attr_added_in("next release")]`
    --> crates\uv-static\src\env_vars.rs:1087:15
     |
1087 |     pub const UV_WORKING_DIRECTORY: &'static str = "UV_WORKING_DIRECTORY";
     |               ^^^^^^^^^^^^^^^^^^^^
error: could not compile `uv-static` (lib) due to 2 previous errors
```

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Closes #15312 
Closes #16237

---------

Co-authored-by: pythonweb2 <32141163+pythonweb2@users.noreply.github.com>
Co-authored-by: Wade Roberts <wade.roberts@centralsquare.com>

Add python-build-standalone 20251010 for CPython 3.12.12, 3.11.14, 3.10.19 and 3.9.24.

Co-authored-by: Geoffrey Thomas <geofft@ldpreload.com>

Co-authored-by: Geoffrey Thomas <geofft@ldpreload.com>