fix(github): support variant in github action and opencode github run (#14431)

github/action.yml

@@ -30,6 +30,10 @@ inputs:
     description: "Comma-separated list of trigger phrases (case-insensitive). Defaults to '/opencode,/oc'"
     required: false
 
+  variant:
+    description: "Model variant for provider-specific reasoning effort (e.g., high, max, minimal)"
+    required: false
+
   oidc_base_url:
     description: "Base URL for OIDC token exchange API. Only required when running a custom GitHub App install. Defaults to https://api.opencode.ai"
     required: false
@@ -71,4 +75,5 @@ runs:
         PROMPT: ${{ inputs.prompt }}
         USE_GITHUB_TOKEN: ${{ inputs.use_github_token }}
         MENTIONS: ${{ inputs.mentions }}
+        VARIANT: ${{ inputs.variant }}
         OIDC_BASE_URL: ${{ inputs.oidc_base_url }}