.tool-versions(uv) uv 0.12.11 -> 0.12.15

why: Use the latest uv release outside the three-day cooldown.

what:
- Update the resolver used by local development and CI.

## Impact

The intervening releases exclude post-cutoff artifacts from lockfiles,
improve cold-cache resolution, and fix symlinked install destinations.

See also:
https://github.com/astral-sh/uv/releases/tag/0.12.12
https://github.com/astral-sh/uv/releases/tag/0.12.15

Author: tony

.tool-versions

@@ -1,3 +1,3 @@
 just 1.58.0
-uv 0.12.11
+uv 0.12.15
 python 3.14 3.13 3.12 3.11 3.10