feat(webui): add subscription tier and quota visualization

Backend:

src/account-manager/storage.js

@@ -31,7 +31,10 @@ export async function loadAccounts(configPath = ACCOUNT_CONFIG_PATH) {
             // Reset invalid flag on startup - give accounts a fresh chance to refresh
             isInvalid: false,
             invalidReason: null,
-            modelRateLimits: acc.modelRateLimits || {}
+            modelRateLimits: acc.modelRateLimits || {},
+            // New fields for subscription and quota tracking
+            subscription: acc.subscription || { tier: 'unknown', projectId: null, detectedAt: null },
+            quota: acc.quota || { models: {}, lastChecked: null }
         }));
 
         const settings = config.settings || {};
@@ -117,7 +120,10 @@ export async function saveAccounts(configPath, accounts, settings, activeIndex)
                 isInvalid: acc.isInvalid || false,
                 invalidReason: acc.invalidReason || null,
                 modelRateLimits: acc.modelRateLimits || {},
-                lastUsed: acc.lastUsed
+                lastUsed: acc.lastUsed,
+                // Persist subscription and quota data
+                subscription: acc.subscription || { tier: 'unknown', projectId: null, detectedAt: null },
+                quota: acc.quota || { models: {}, lastChecked: null }
             })),
             settings: settings,
             activeIndex: activeIndex

src/cloudcode/index.js

@@ -12,17 +12,18 @@
 // Re-export public API
 export { sendMessage } from './message-handler.js';
 export { sendMessageStream } from './streaming-handler.js';
-export { listModels, fetchAvailableModels, getModelQuotas } from './model-api.js';
+export { listModels, fetchAvailableModels, getModelQuotas, getSubscriptionTier } from './model-api.js';
 
 // Default export for backwards compatibility
 import { sendMessage } from './message-handler.js';
 import { sendMessageStream } from './streaming-handler.js';
-import { listModels, fetchAvailableModels, getModelQuotas } from './model-api.js';
+import { listModels, fetchAvailableModels, getModelQuotas, getSubscriptionTier } from './model-api.js';
 
 export default {
     sendMessage,
     sendMessageStream,
     listModels,
     fetchAvailableModels,
-    getModelQuotas
+    getModelQuotas,
+    getSubscriptionTier
 };

src/cloudcode/model-api.js

@@ -110,3 +110,75 @@ export async function getModelQuotas(token) {
 
     return quotas;
 }
+
+/**
+ * Get subscription tier for an account
+ * Calls loadCodeAssist API to discover project ID and subscription tier
+ *
+ * @param {string} token - OAuth access token
+ * @returns {Promise<{tier: string, projectId: string|null}>} Subscription tier (free/pro/ultra) and project ID
+ */
+export async function getSubscriptionTier(token) {
+    const headers = {
+        'Authorization': `Bearer ${token}`,
+        'Content-Type': 'application/json',
+        ...ANTIGRAVITY_HEADERS
+    };
+
+    for (const endpoint of ANTIGRAVITY_ENDPOINT_FALLBACKS) {
+        try {
+            const url = `${endpoint}/v1internal:loadCodeAssist`;
+            const response = await fetch(url, {
+                method: 'POST',
+                headers,
+                body: JSON.stringify({
+                    metadata: {
+                        ideType: 'IDE_UNSPECIFIED',
+                        platform: 'PLATFORM_UNSPECIFIED',
+                        pluginType: 'GEMINI'
+                    }
+                })
+            });
+
+            if (!response.ok) {
+                logger.warn(`[CloudCode] loadCodeAssist error at ${endpoint}: ${response.status}`);
+                continue;
+            }
+
+            const data = await response.json();
+
+            // Extract project ID
+            let projectId = null;
+            if (typeof data.cloudaicompanionProject === 'string') {
+                projectId = data.cloudaicompanionProject;
+            } else if (data.cloudaicompanionProject?.id) {
+                projectId = data.cloudaicompanionProject.id;
+            }
+
+            // Extract subscription tier (priority: paidTier > currentTier)
+            let tier = 'free';
+            const tierId = data.paidTier?.id || data.currentTier?.id;
+
+            if (tierId) {
+                const lowerTier = tierId.toLowerCase();
+                if (lowerTier.includes('ultra')) {
+                    tier = 'ultra';
+                } else if (lowerTier.includes('pro')) {
+                    tier = 'pro';
+                } else {
+                    tier = 'free';
+                }
+            }
+
+            logger.debug(`[CloudCode] Subscription detected: ${tier}, Project: ${projectId}`);
+
+            return { tier, projectId };
+        } catch (error) {
+            logger.warn(`[CloudCode] loadCodeAssist failed at ${endpoint}:`, error.message);
+        }
+    }
+
+    // Fallback: return default values if all endpoints fail
+    logger.warn('[CloudCode] Failed to detect subscription tier from all endpoints. Defaulting to free.');
+    return { tier: 'free', projectId: null };
+}

src/server.js

@@ -8,7 +8,7 @@ import express from 'express';
 import cors from 'cors';
 import path from 'path';
 import { fileURLToPath } from 'url';
-import { sendMessage, sendMessageStream, listModels, getModelQuotas } from './cloudcode/index.js';
+import { sendMessage, sendMessageStream, listModels, getModelQuotas, getSubscriptionTier } from './cloudcode/index.js';
 import { mountWebUI } from './webui/index.js';
 import { config } from './config.js';
 
@@ -266,11 +266,33 @@ app.get('/account-limits', async (req, res) => {
 
                 try {
                     const token = await accountManager.getTokenForAccount(account);
-                    const quotas = await getModelQuotas(token);
+
+                    // Fetch both quotas and subscription tier in parallel
+                    const [quotas, subscription] = await Promise.all([
+                        getModelQuotas(token),
+                        getSubscriptionTier(token)
+                    ]);
+
+                    // Update account object with fresh data
+                    account.subscription = {
+                        tier: subscription.tier,
+                        projectId: subscription.projectId,
+                        detectedAt: Date.now()
+                    };
+                    account.quota = {
+                        models: quotas,
+                        lastChecked: Date.now()
+                    };
+
+                    // Save updated account data to disk (async, don't wait)
+                    accountManager.saveToDisk().catch(err => {
+                        logger.error('[Server] Failed to save account data:', err);
+                    });
 
                     return {
                         email: account.email,
                         status: 'ok',
+                        subscription: account.subscription,
                         models: quotas
                     };
                 } catch (error) {
@@ -278,6 +300,7 @@ app.get('/account-limits', async (req, res) => {
                         email: account.email,
                         status: 'error',
                         error: error.message,
+                        subscription: account.subscription || { tier: 'unknown', projectId: null },
                         models: {}
                     };
                 }
@@ -451,6 +474,8 @@ app.get('/account-limits', async (req, res) => {
                     invalidReason: metadata.invalidReason || null,
                     lastUsed: metadata.lastUsed || null,
                     modelRateLimits: metadata.modelRateLimits || {},
+                    // Subscription data (new)
+                    subscription: acc.subscription || metadata.subscription || { tier: 'unknown', projectId: null },
                     // Quota limits
                     limits: Object.fromEntries(
                         sortedModels.map(modelId => {