[BugFix] Restore free-threaded (cp314t) wheel builds

[kostasrigatos]

Description

Addresses #4499 (see note on cp313t below).

I checked generate_binary_build_matrix.py. There's no special setting for free-threaded builds — the system detects them only if a Python version string has a t suffix, e.g. 3.14t. PR #3799 replaced this list with a hard-coded version and removed all t-versions, with no explanation. This broke the free-threaded builds.

Motivation and Context

Issue with Python 3.13t: The docker image of PyTorch's manylinux2_28-builder:cpu includes cp314t and cp315t, but not cp313t. I checked directly via docker pull and ls /opt/python/. 3.13t cannot be fixed by editing workflow files, because the required Python version is missing from the build image.

Fix: I added 3.14t back to the python-versions list. This applies to all build-wheels-*.yml workflows, namely Linux, aarch64, M1, and Windows. I did not add 3.13t, since its addition would just cause the build to fail.

Testing: confirmed via workflow_dispatch on this branch that generate-matrix correctly expands 3.14t into a real matrix entry (build-manywheel-py3_14t-cpu). I wasn't able to verify the actual wheel build completes — build_wheels_linux.yml targets PyTorch's self-hosted runner pool, which isn't reachable from a fork — so this needs CI on the PR itself to confirm.

AI disclosure: I used Claude for design discussion, code review, debugging guidance, and drafting this PR description. All code was written by me; nothing in this PR was generated by an agent. I've read, run, and understood every change myself.

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[pytorch-bot]

🔗 Helpful Links

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⚠️ 16 Awaiting Approval

As of commit 3f99224 with merge base 7040ad0 ():

AWAITING APPROVAL - The following workflows need approval before CI can run:

• Build Aarch64 Linux Wheels (gh)
• Build Linux Wheels (gh)
• Build M1 Wheels (gh)
• Build Windows Wheels (gh)
• Continuous Benchmark (PR) (gh)
• Examples Tests on Linux (gh)
• Generate documentation (gh)
• Habitat Tests on Linux (gh)
• Libs Tests on Linux (gh)
• Lint (gh)
• LLM Tests on Linux (gh)
• Push Binary Nightly (gh)
• SOTA Tests on Linux (gh)
• Tutorials Tests on Linux (gh)
• Unit-tests on Linux (gh)
• Validate Test Partitioning (gh)

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