feat: 拆分 providers.json 为按 Provider 独立文件

将 compute/providers.json（54KB, 14 providers, 99 models）拆分为
compute/providers/ 目录下的独立 JSON 文件，便于维护和按需更新。

新增文件：
- compute/providers/_index.json — 加载顺序索引（保证 digest 确定性）
- compute/providers/{provider}.json × 14 — 各 provider 独立配置

保留 compute/providers.json 供旧客户端向后兼容（过渡期）。

presetDataVersion: 2 → 3

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

compute/providers/baichuan.json

@@ -0,0 +1,90 @@
+{
+  "id": "provider-baichuan-001",
+  "provider": "baichuan",
+  "label": "百川智能",
+  "baseUrl": "https://api.baichuan-ai.com/v1",
+  "apiFormat": "openai-completions",
+  "apiKeyRef": "baichuan",
+  "apiKeyVerified": false,
+  "enabled": false,
+  "status": "unconfigured",
+  "services": [
+    "chat"
+  ],
+  "defaultTemperature": 0.7,
+  "defaultTopP": 0.9,
+  "models": [
+    {
+      "modelName": "Baichuan-M3-Plus",
+      "displayName": "百川 M3-Plus",
+      "serviceType": "chat",
+      "description": "百川智能M3-Plus医疗增强模型，235B参数，幻觉率仅2.6%，API价格较前代下降70%",
+      "contextWindow": 192000,
+      "maxOutputTokens": 8192,
+      "capabilities": [
+        "chat",
+        "reasoning",
+        "code",
+        "multilingual",
+        "long_context",
+        "medical"
+      ],
+      "inputPrice": 1.5,
+      "outputPrice": 4.5,
+      "extra": {}
+    },
+    {
+      "modelName": "Baichuan-M3",
+      "displayName": "百川 M3",
+      "serviceType": "chat",
+      "description": "百川智能M3新一代开源医疗增强模型，235B参数",
+      "contextWindow": 192000,
+      "maxOutputTokens": 8192,
+      "capabilities": [
+        "chat",
+        "reasoning",
+        "code",
+        "multilingual",
+        "medical"
+      ],
+      "inputPrice": 2,
+      "outputPrice": 6,
+      "extra": {}
+    },
+    {
+      "modelName": "Baichuan-M2-Plus",
+      "displayName": "百川 M2-Plus",
+      "serviceType": "chat",
+      "description": "百川智能M2-Plus旗舰模型，最强推理和创作能力",
+      "contextWindow": 128000,
+      "maxOutputTokens": 8192,
+      "capabilities": [
+        "chat",
+        "reasoning",
+        "code",
+        "multilingual",
+        "long_context"
+      ],
+      "inputPrice": 5,
+      "outputPrice": 15,
+      "extra": {}
+    },
+    {
+      "modelName": "Baichuan-M2",
+      "displayName": "百川 M2",
+      "serviceType": "chat",
+      "description": "百川智能M2模型，高性能通用模型",
+      "contextWindow": 128000,
+      "maxOutputTokens": 8192,
+      "capabilities": [
+        "chat",
+        "reasoning",
+        "code",
+        "multilingual"
+      ],
+      "inputPrice": 3,
+      "outputPrice": 9,
+      "extra": {}
+    }
+  ]
+}