Update reasoning effort explanation in README

Author: DanWahlin

01-setup-and-first-steps/README.md

@@ -469,7 +469,7 @@ copilot
 
 > 💡 **Tip**: Some models cost more "premium requests" than others. Models marked **1x** (like Claude Sonnet 4.5) are a great default. They're capable and efficient. Higher-multiplier models use your premium request quota faster, so save those for when you really need them.
 
-> 💡 **Reasoning effort**: Inside the model picker, use the ← and → arrow keys to adjust the **reasoning effort** for the selected model. Lower effort is faster; higher effort is more thorough. The current effort level is shown next to the model name in the session header (e.g., `claude-sonnet-4.5 (high)`). Start with the default and raise it only when you need deeper analysis.
+> 💡 **Reasoning effort**: Inside the model picker, use the ← and → arrow keys to adjust the **reasoning effort** for the selected model (if supported). Lower effort is faster; higher effort is more thorough. The current effort level is shown next to the model name in the session header (e.g., `claude-sonnet-4.5 (high)`). Start with the default and raise it only when you need deeper analysis.
 
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