Add BOM output, fix LTspice Tier 2 import, real .asc integration tests

- Fix _try_ltspice_generation() to use spicelib.simulators.ltspice_simulator.LTspice
  instead of the abstract Simulator base class (which always returned unavailable)
- Use LTspice.create_netlist() instead of Simulator.run() for correct netlist generation
- Add --ltspice-exe CLI option to specify LTspice binary path
- Add --bom flag for component BOM CSV output (works on any parse completeness)
- Add --bom-wiring flag for wiring BOM CSV from mapped output
- Add real 1002A.asc demo circuit and pre-generated .net as test fixtures
- Add @pytest.mark.ltspice marker for tests requiring LTspice binary
- Bump version to 2026.2.14

tests/test_cli.py

@@ -14,7 +14,7 @@ class TestCLIBasic:
         runner = CliRunner()
         result = runner.invoke(main, ["--version"])
         assert result.exit_code == 0
-        assert "2026.2.13" in result.output
+        assert "2026.2.14" in result.output
 
     def test_list_subcircuits(self):
         runner = CliRunner()