feat: 添加模型上下文管理并统一主题组件与用量交互

frontend/src/contracts/index.ts

@@ -96,6 +96,7 @@ export interface Citation {
 // ============ Model Events (SSE) ============
 
 export type ModelEventType =
+  | 'ContextStatus'
   | 'TextDelta'
   | 'ThinkingDelta'
   | 'ToolCallStart'
@@ -404,8 +405,18 @@ export interface RequestOverride {
   body: Record<string, unknown>
 }
 
+export interface ModelContextPolicy {
+  model: string
+  context_window: number
+  output_reserve: number
+  threshold: number
+  mode: 'detect' | 'compress'
+  prompt: string
+}
+
 export interface ProviderConfig {
   version?: number
+  context_policies?: ModelContextPolicy[]
   request_overrides?: RequestOverride[]
   provider_id: string
   provider_type: ProviderType
@@ -747,6 +758,7 @@ export type ApiProviderType =
 
 export interface ApiProviderConfig {
   version?: number
+  context_policies?: ModelContextPolicy[]
   request_overrides?: RequestOverride[]
   provider_id: string
   provider_type: ApiProviderType