Merge PR #1300: tailscale Windows fix, quota pagination, SSE abort handling

- fix(tunnel): cross-platform tailscale probes without shell redirection
- feat(usage): paginate provider limits with page size controls
- feat(providers): stop control for one-by-one connection testing
- fix(sse): close stream gracefully on abort/disconnect instead of pipe errors
- ui(quota): simplify header, always show pagination in one row

Co-authored-by: philau2512 <dplau25122002@gmail.com>
Co-authored-by: Cursor <cursoragent@cursor.com>

src/app/(dashboard)/dashboard/usage/components/ProviderLimits/utils.js

@@ -75,6 +75,23 @@ export function calculatePercentage(used, total) {
   return Math.round(((total - used) / total) * 100);
 }
 
+/**
+ * Get remaining percentage from a normalized quota row
+ * @param {Object} quota - Normalized quota object
+ * @returns {number} Remaining percentage (0-100)
+ */
+export function getRemainingPercentage(quota) {
+  if (quota?.remaining !== undefined) {
+    return Math.max(0, Math.round(quota.remaining));
+  }
+
+  if (quota?.remainingPercentage !== undefined) {
+    return Math.round(quota.remainingPercentage);
+  }
+
+  return calculatePercentage(quota?.used, quota?.total);
+}
+
 /**
  * Parse provider-specific quota structures into normalized array
  * @param {string} provider - Provider name (github, antigravity, codex, kiro, claude)
@@ -123,6 +140,7 @@ export function parseQuotaData(provider, data) {
               name: quotaType,
               used: quota.used || 0,
               total: quota.total || 0,
+              remaining: quota.remaining,
               resetAt: quota.resetAt || null,
             });
           });