Add a context percentage threshold setting for auto compression (#5721)

packages/core/src/config/config.ts

@@ -69,6 +69,10 @@ export interface BugCommandSettings {
   urlTemplate: string;
 }
 
+export interface ChatCompressionSettings {
+  contextPercentageThreshold?: number;
+}
+
 export interface SummarizeToolOutputSettings {
   tokenBudget?: number;
 }
@@ -191,6 +195,7 @@ export interface ConfigParameters {
   folderTrustFeature?: boolean;
   ideMode?: boolean;
   loadMemoryFromIncludeDirectories?: boolean;
+  chatCompression?: ChatCompressionSettings;
 }
 
 export class Config {
@@ -252,6 +257,7 @@ export class Config {
     | undefined;
   private readonly experimentalAcp: boolean = false;
   private readonly loadMemoryFromIncludeDirectories: boolean = false;
+  private readonly chatCompression: ChatCompressionSettings | undefined;
 
   constructor(params: ConfigParameters) {
     this.sessionId = params.sessionId;
@@ -316,6 +322,7 @@ export class Config {
     }
     this.loadMemoryFromIncludeDirectories =
       params.loadMemoryFromIncludeDirectories ?? false;
+    this.chatCompression = params.chatCompression;
 
     if (params.contextFileName) {
       setGeminiMdFilename(params.contextFileName);
@@ -667,6 +674,10 @@ export class Config {
     return this.ideClient;
   }
 
+  getChatCompression(): ChatCompressionSettings | undefined {
+    return this.chatCompression;
+  }
+
   async getGitService(): Promise<GitService> {
     if (!this.gitService) {
       this.gitService = new GitService(this.targetDir);