feat: implement granular access revocation and global unsharing in the account permissions dialog

frontend/electron/services/backend.ts

@@ -61,7 +61,8 @@ export class BackendService {
         gameBans: account.gameBans,
         loginName: account.loginName,
         steamLoginSecure: account.steamLoginSecure,
-        loginConfig: account.loginConfig
+        loginConfig: account.loginConfig,
+        sessionUpdatedAt: account.sessionUpdatedAt
       }, { headers: this.headers });
     } catch (e) {
       console.error('[Backend] Failed to share account');
@@ -91,4 +92,31 @@ export class BackendService {
       throw new Error(e.response?.data?.message || 'Failed to share account');
     }
   }
+
+  public async revokeAccess(steamId: string, targetSteamId: string) {
+    if (!this.token) return;
+    try {
+      const response = await axios.delete(`${this.url}/api/sync/${steamId}/share`, {
+        headers: this.headers,
+        data: { targetSteamId }
+      });
+      return response.data;
+    } catch (e: any) {
+      console.error(`[Backend] Failed to revoke access for ${steamId} from ${targetSteamId}`);
+      throw new Error(e.response?.data?.message || 'Failed to revoke access');
+    }
+  }
+
+  public async revokeAllAccess(steamId: string) {
+    if (!this.token) return;
+    try {
+      const response = await axios.delete(`${this.url}/api/sync/${steamId}/share/all`, {
+        headers: this.headers
+      });
+      return response.data;
+    } catch (e: any) {
+      console.error(`[Backend] Failed to revoke all access for ${steamId}`);
+      throw new Error(e.response?.data?.message || 'Failed to revoke all access');
+    }
+  }
 }