Drop 3.13t from the wheel matrix; run twine via python -m

NumPy >= 2.5 ships no cp313t wheels on any platform, so the 3.13t builds
had to compile NumPy from source: macOS failed outright, Windows took six
minutes for the NumPy build alone, and Linux aarch64 under QEMU was still
running after an hour. Only 3.14t is built now.

The macOS 3.14t job built and tested both wheels fine (GIL stays disabled
on x86_64 and arm64) but then failed in the twine step with
"pip: command not found". Call pip and twine via python -m so the step
does not depend on a pip launcher being on PATH.

Co-Authored-By: Claude Fable 5.1 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_013aQs1u37EG6XTHFrcaBRkA

Author: dance858

.github/workflows/build-and-publish.yml

@@ -33,13 +33,16 @@ jobs:
         os: [ ubuntu-22.04, macos-14, windows-2022 ]
         python-version: [ "3.11", "3.12", "3.13", "3.14" ]
         # "" builds the default (GIL) interpreter, "t" the free-threaded one.
-        # Free-threaded CPython exists from 3.13 onwards.
+        # Only 3.14t: NumPy >= 2.5 ships no cp313t wheels on any platform, so a
+        # 3.13t build would have to compile NumPy from source.
         abi: [ "", "t" ]
         exclude:
           - python-version: "3.11"
             abi: "t"
           - python-version: "3.12"
             abi: "t"
+          - python-version: "3.13"
+            abi: "t"
 
     env:
       PYTHON_VERSION: ${{ matrix.python-version }}
@@ -86,8 +89,8 @@ jobs:
       - name: Check wheels
         shell: bash
         run: |
-          pip install --upgrade twine
-          twine check wheelhouse/*
+          python -m pip install --upgrade twine
+          python -m twine check wheelhouse/*
 
       - uses: actions/upload-artifact@v4
         with:

README.md

@@ -16,8 +16,9 @@ from sparsediffpy import _sparsediffengine
 
 ## Free-threaded Python
 
-Wheels are published for the free-threaded CPython builds (`cp313t`, `cp314t`) as
-well as the default ones. The extension declares that it does not need the GIL:
+Wheels are published for free-threaded CPython 3.14 (`cp314t`) as well as the
+default builds. There is no 3.13t wheel because NumPy 2.5 and later ship no
+`cp313t` wheels. The extension declares that it does not need the GIL:
 the engine keeps no global mutable state, every problem and expression owns its
 own buffers, and all inputs and outputs are copied at the boundary. Distinct
 problems can therefore be built and evaluated concurrently from different