Bump pydantic to 2.12.5 for CPython 3.14 wheels

The pinned pydantic==2.11.7 resolves pydantic-core 2.33.2, which has no
prebuilt wheel for CPython 3.14. The Home Assistant add-on image moved to
Alpine/Python 3.14 and installs our packages from pyproject (not the lockfile),
so pip fell back to compiling pydantic-core from Rust source and failed for
lack of a toolchain. pydantic 2.12.5 pulls pydantic-core 2.41.5, which ships
cp314-cp314 musllinux wheels for x86_64/aarch64/armv7l, so no source build is
needed. Tests and strict mypy pass on the new versions.

Author: jfmlima

packages/core/pyproject.toml

@@ -10,7 +10,7 @@ authors = [{name = "Jorge Lima", email = "jorgefilipemlima@gmail.com"}]
 readme = "README.md"
 requires-python = ">=3.11"
 dependencies = [
-    "pydantic==2.11.7",
+    "pydantic==2.12.5",
     "pydantic-settings==2.10.1",
     "structlog==25.4.0",
     "httpx==0.28.1",