Make CI actually run, and go green

[saudzahirr]

Summary

CI had never executed on this repository — gh run list --workflow=code_test.yml showed zero runs before this branch. Fixing that surfaced two further failures that the first bug had been hiding. Three fixes, each uncovered by the one before it:

1. Workflows never triggered (3caeeb8)
The default branch is master, but push/pull_request triggers in code_style.yml, code_test.yml and docs_build.yml were filtered to main, which does not exist here. No event ever matched.

2. Codecov failed the whole matrix (74734f5)
With CI finally running, every testing job passed its suite and then died on the upload step:

error -- Upload queued for processing failed: {"message":"Repository not found"}  (HTTP 404)

eggzec/brayer is not activated on Codecov and there is no CODECOV_TOKEN secret, so fail_ci_if_error: true turned a reporting outage into a build failure. Coverage upload is now best-effort; the test run is the gate.

3. Python 3.14 could not install dependencies (c20dd43)
All three 3.14 jobs failed before running any test:

error: the configured Python interpreter version (3.14) is newer than
       PyO3's maximum supported version (3.13)
       Current version: 0.24.1

uv.lock pinned pydantic 2.11.7 → pydantic-core 2.33.2, which ships no cp314 wheel, so uv built it from source and hit that version's PyO3 ceiling. pyproject.toml only requires pydantic>=2.7, so the stale lock was the only constraint. Relocked to pydantic 2.13.4 / pydantic-core 2.46.4, which publishes cp314 wheels for every matrix platform.

Test plan

• All 12 checks pass on this PR: the full 9-job matrix (3.10–3.14 across ubuntu/windows/macos), setup, fresh_build / build, and Build Documentation.
• Suite run locally against the upgraded pydantic: 130 passed.
• Lint and Format is correctly absent — its paths: ['**/*.py'] filter excludes this PR, which touches no Python.

Follow-up (not in this PR)

To get coverage data flowing again, activate eggzec/brayer at codecov.io. .codecov.yml (90% project / 70% patch) and the README badge are already in place and will start working once onboarded.

🤖 Generated with Claude Code

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