chore(ci): run the suite on Python 3.11 and 3.12

[fer1994]

Problem

The project supports Python 3.11 through 3.14 but only ever executes its tests on the newest two. This is an internal inconsistency rather than a matter of taste:

File	Python matrix
pyproject.toml	requires-python = ">=3.11"
.github/workflows/security.yml	["3.11", "3.12", "3.13", "3.14"]
.github/workflows/test.yml	["3.13", "3.14"]

The scheduled dependency audit already treats 3.11–3.14 as the supported matrix, and tests/test_security_workflow.py::test_scheduled_dependency_audit_runs_supported_python_os_matrix asserts exactly that list. Meanwhile the older half of the range ships without a single test execution behind it.

The floor is genuine rather than vestigial: tomllib in src/specify_cli/_assets.py:111 is the only 3.11+ API in the source, so 3.11 is exactly the right minimum — it simply is not covered.

Evidence

Both added interpreters pass the full suite today, so this closes a coverage gap rather than introducing failures. Run locally on macOS 15 (arm64) against a2c1843:

Interpreter	Result
CPython 3.11.16	8176 passed, 208 skipped
CPython 3.12.14	8176 passed, 208 skipped
CPython 3.13.15	8176 passed, 208 skipped

Cost

Added through include on ubuntu-latest only, which takes the matrix from 6 jobs to 8 rather than to 12. The OS-specific paths on macOS and Windows stay covered by 3.13/3.14; what 3.11 and 3.12 add is interpreter coverage, which is not OS-dependent for this codebase.

If the two extra jobs are unwelcome, the alternative worth considering is the opposite direction — raise requires-python to >=3.13 and stop claiming support for versions nobody tests. Either resolves the inconsistency; leaving it as-is does not. Happy to switch this PR to that shape instead if maintainers prefer it.

AI disclosure

Written with Claude Code (Opus 5). The inconsistency was found by reading the three files against each other, and each added interpreter was installed and run through the full suite locally before the matrix was touched. I reviewed the change and re-ran the evidence against current main before opening this.