Remove GPT 5 mini from the auto model pool and other misc changes (#60043)

Co-authored-by: Ben Ahmady <32935794+subatoi@users.noreply.github.com>

Author: nhu-do

content/copilot/concepts/auto-model-selection.md

@@ -41,7 +41,6 @@ With {% data variables.copilot.copilot_auto_model_selection %}, you benefit from
 
 When you select **Auto** in {% data variables.copilot.copilot_chat_short %}, {% data variables.copilot.copilot_auto_model_selection_short_cap_a %} may choose from the following list of models, subject to your policies and subscription type. Models may change over time.
   * {% data variables.copilot.copilot_gpt_41 %}
-  * {% data variables.copilot.copilot_gpt_5_mini %}
   * {% data variables.copilot.copilot_gpt_52_codex %}
   * {% data variables.copilot.copilot_gpt_53_codex %}
   * {% data variables.copilot.copilot_claude_haiku_45 %}

data/tables/copilot/model-multipliers.yml

@@ -95,7 +95,7 @@
 
 - name: Grok Code Fast 1
   multiplier_paid: 0.25
-  multiplier_free: Not applicable
+  multiplier_free: 1
 
 - name: Raptor mini
   multiplier_paid: 0

data/tables/copilot/model-supported-plans.yml

@@ -153,7 +153,7 @@
   enterprise: true
 
 - name: Grok Code Fast 1
-  free: false
+  free: true
   pro: true
   pro_plus: true
   business: true