feat: 优化模型分层并新增 gpt-5.1-codex-mini

oh-my-opencode.jsonc

@@ -4,7 +4,8 @@
   "agents": {
     // ref: https://github.com/code-yeongyu/oh-my-opencode/blob/dev/AGENTS.md#agent-models
     "sisyphus": {
-      "model": "glm-coding-plan/glm-4.7"
+      "model": "codex/gpt-5.3-codex",
+      "variant": "high"
     },
     "hephaestus": {
       "model": "codex/gpt-5.3-codex",
@@ -21,7 +22,8 @@
       "model": "glm-coding-plan/glm-4.7"
     },
     "multimodal-looker": {
-      "model": "codex/gpt-5.2"
+      "model": "codex/gpt-5.2",
+      "variant": "medium"
     },
     "prometheus": {
       "model": "codex/gpt-5.2",
@@ -36,13 +38,15 @@
       "variant": "medium"
     },
     "atlas": {
-      "model": "codex/gpt-5.2"
+      "model": "codex/gpt-5.2",
+      "variant": "medium"
     }
   },
   "categories": {
     // ref: https://github.com/code-yeongyu/oh-my-opencode/blob/dev/docs/category-skill-guide.md#available-built-in-categories
     "visual-engineering": {
-      "model": "glm-coding-plan/glm-4.7"
+      "model": "codex/gpt-5.2",
+      "variant": "medium"
     },
     "ultrabrain": {
       "model": "codex/gpt-5.3-codex",
@@ -56,12 +60,12 @@
       "model": "glm-coding-plan/glm-4.7"
     },
     "unspecified-low": {
-      "model": "codex/gpt-5.3-codex",
+      "model": "codex/gpt-5.2",
       "variant": "medium"
     },
     "unspecified-high": {
       "model": "codex/gpt-5.3-codex",
-      "variant": "medium"
+      "variant": "high"
     },
     "writing": {
       "model": "glm-coding-plan/glm-4.7"