[Misc] Add test verifying static if dead branch is not compiled.

[hughperkins]

Places an unsupported import statement in the dead branch of a qd.static(True) / qd.static(False) if-statement. If the transformer incorrectly walks the dead branch, it raises QuadrantsSyntaxError.

Issue: #

Brief Summary

copilot:summary

Walkthrough

copilot:walkthrough

[hughperkins]

Opus 4.6 review:

This is a very focused branch — just 1 commit of actual new work (plus a merge commit bringing in latest main). The sole change is a new test in tests/python/test_static.py.
What the test does:
test_static_if_dead_branch_not_walked verifies that when qd.static(True) or qd.static(False) is used in an if statement, the dead (not-taken) branch is not walked by the AST
transformer. It proves this by placing an import os statement in the dead branch — since import is unsupported by the AST transformer and would raise a QuadrantsSyntaxError, the
test would fail if the dead branch were visited. It then asserts the live branch executed correctly.
Thoughts:

1. Clean and well-scoped. The test is a clear, minimal reproduction that directly targets the behavior it's testing. Using an unsupported AST construct (import) as the canary
   is a clever, lightweight way to verify the dead branch is truly skipped.
2. Good coverage of both directions. It tests both static(True) (else-branch dead) and static(False) (if-branch dead), which is thorough.
3. No implementation change. This is a pure test addition — it seems like it's verifying existing behavior rather than accompanying a code fix. That's fine as a regression
   guard, but it's worth confirming: is this documenting already-working behavior, or was there a recent fix on main that this is meant to cover?
4. Minor nit: The # noqa: F401 comments are a nice touch to suppress unused-import linter warnings.

Overall, it's a solid, targeted test. Ready to merge as-is.