[codex] Bootstrap HFSS plugin

[jiweiqi]

Summary

Bootstrap sim-plugin-hfss as an initial Ansys HFSS 3D plugin for sim-cli, with local AEDT smoke validation completed.

This PR adds an installable plugin package with:

• sim entry points for driver, bundled skill, and plugin metadata
• an import-safe HfssDriver with lazy PyAEDT integration
• layered AEDT discovery through explicit env vars, Ansys env vars, generic launchers on PATH, and conservative default install probes
• detected install metadata with an explicit launch override when needed
• a small runtime surface: detect, connect, run snippet/script, inspect, disconnect
• no-AEDT unit tests plus opt-in real HFSS smoke coverage
• a manual PyPI release workflow matching the existing plugin release pattern
• public README, notice, changelog, and CI

Scope

Version 0.1.0 targets HFSS 3D through PyAEDT. It intentionally does not cover HFSS 3D Layout, Maxwell, Icepak, Q3D, Circuit, direct .aedt/.aedtz batch solving, or plugin-index catalogue updates before the public package is live and smoke-tested.

The driver keeps workflow specifics in agent-authored PyAEDT snippets/scripts rather than adding plugin-specific geometry, port, solve, or export methods.

Local Validation

• uv sync --extra test passed
• uv lock --check passed
• uv run pytest -q --basetemp .pytest_basetemp/local passed: 34 passed, 1 skipped
• uv build passed and produced sdist + wheel
• uv run sim check hfss detected AEDT 2025.2 through default discovery
• opt-in real smoke passed: SIM_HFSS_RUN_INTEGRATION=1 uv run pytest tests/test_hfss_real_smoke.py -q --basetemp .pytest_basetemp/hfss-real
• CLI smoke passed: sim connect --solver hfss --ui-mode no_gui, inspect session.summary, inspect hfss.project.identity, inspect hfss.design.summary, bounded PyAEDT exec, and disconnect --stop-server
• Tiny HFSS smoke evidence: design SimSmoke, solution type Eigenmode, object SimSmokeBox, setup SimSmokeSetup, setup_created=true, solve_ok=true
• PyPI availability probe confirmed sim-plugin-hfss 0.1.0 is not already published
• git diff --check passed

CI

GitHub Actions ci passed on commit 8c4e8cabbc06e03103fd95a6cde483d148038a70:

• test (3.10): success
• test (3.12): success

Notes

A PyAEDT 0.26.x startup compatibility shim is included for edition-suffixed AEDT version strings. Detailed environment-specific validation notes are tracked in the internal issue.

Still Gated

• Merge, tag, and PyPI publish are intentionally held for human approval.
• Fresh PyPI install smoke and sim-plugin-index addition are deferred until after the PyPI package is live.