[ChiselSim] Flag `--trace-threads` is deprecated since Verilator v5.048

**Type of issue**: Bug Report

**Please provide the steps to reproduce the problem:**

1. Install `verilator` v5.048 or later
2. Write a ChiselSim test with a `CompilationSettings` of
```scala
CompilationSettings.default.withTraceStyle(Some(CompilationSettings.TraceStyle(CompilationSettings.TraceKind.Fst(Some(2)))))
```
The test content doesn't matter
3. The test fails even if no `expect` is violated

**What is the current behavior?**

Currently the Test would fail with message below:
```
%Warning-DEPRECATED: Option '--trace-threads' is deprecated and has no effect.
... For warning description see https://verilator.org/warn/DEPRECATED?v=5.048
... Use "/* verilator lint_off DEPRECATED */" and lint_on around source to disable this message.
%Error: Exiting due to 1 warning(s)
make[1]: *** [Makefile:12: simulation] Error 1
```

**What is the expected behavior?**

The test should pass without any issue

**Please tell us about your environment:**

- version: `7.11.0`
- OS: `Linux 6.6.114.1-microsoft-standard-WSL2 #1 SMP PREEMPT_DYNAMIC Mon Dec 1 20:46:23 UTC 2025 x86_64 GNU/Linux`

**Other Information**

None

**What is the use case for changing the behavior?**

I suggest that ChiselSim should be able to support newer Verilator versions for rolling-released systems like Arch Linux to work properly

Reproduce the failure with Verilator v5.048 or later using ChiselSim's CompilationSettings.default.withTraceStyle and TraceKind.Fst(Some(2)). Trace where the --trace-threads option is emitted for this configuration; done means the simulation passes without the deprecation warning while preserving the requested trace behavior.

Written by the indexing model from the issue text.