feat(oauth): add OAuth token support

ts/bunq.classes.session.ts

@@ -13,6 +13,7 @@ export class BunqSession {
   private crypto: BunqCrypto;
   private context: IBunqApiContext;
   private sessionExpiryTime: plugins.smarttime.TimeStamp;
+  private isOAuthMode: boolean = false;
 
   constructor(crypto: BunqCrypto, context: IBunqApiContext) {
     this.crypto = crypto;
@@ -139,10 +140,27 @@ export class BunqSession {
     this.sessionExpiryTime = plugins.smarttime.TimeStamp.fromMilliSeconds(Date.now() + 600000);
   }
 
+  /**
+   * Set OAuth mode
+   */
+  public setOAuthMode(isOAuth: boolean): void {
+    this.isOAuthMode = isOAuth;
+    if (isOAuth) {
+      // OAuth tokens don't expire in the same way as regular sessions
+      // Set a far future expiry time
+      this.sessionExpiryTime = plugins.smarttime.TimeStamp.fromMilliSeconds(Date.now() + 365 * 24 * 60 * 60 * 1000);
+    }
+  }
+
   /**
    * Check if session is still valid
    */
   public isSessionValid(): boolean {
+    // OAuth tokens are always considered valid (they have their own expiry mechanism)
+    if (this.isOAuthMode) {
+      return true;
+    }
+    
     if (!this.sessionExpiryTime) {
       return false;
     }
@@ -155,6 +173,11 @@ export class BunqSession {
    * Refresh the session if needed
    */
   public async refreshSession(): Promise<void> {
+    // OAuth tokens don't need session refresh
+    if (this.isOAuthMode) {
+      return;
+    }
+    
     if (!this.isSessionValid()) {
       await this.createSession();
     }