docs(utest): Add standardized documentation for core.irq (irq_tc.c) (#10913)

* docs(utest): Add standardized documentation for core.irq (irq_tc.c)

Most test cases in `src/utest` lack standardized functional
documentation, as tracked in issue #10895. This leads to high
maintenance costs, difficulty for new contributors, and inefficient
code reviews.

Solution:
This patch adds the full, standardized documentation block to
`src/utest/irq_tc.c`, following the approved template.

The documentation details:
- Test Objectives and tested APIs
- Test Scenarios (for `irq_test` and `interrupt_test`)
- Verification Metrics (the `uassert` criteria)
- Dependencies (Kconfig options and hardware)
- Test Execution command and Expected Results

This makes the test case's purpose and behavior immediately clear
to future maintainers and reviewers.

Relates to #10895

Signed-off-by: lhxj <[email protected]>

* Update src/utest/irq_tc.c

Co-authored-by: Copilot <[email protected]>

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Signed-off-by: lhxj <[email protected]>
Co-authored-by: Copilot <[email protected]>

0 files changed, 0 insertions, 0 deletions