feat(quota): add NanoGPT quota provider support (#424)

* feat: add NanoGPT quota provider and usage fetch

Detect NanoGPT as a configured quota provider.
Expose daily and monthly usage windows with reset times.
Return configured and ok state based on API key presence.

* feat: fetch NanoGPT quota and detect config

Detect NanoGPT in configured providers from auth.
Fetch and expose daily and monthly usage windows for NanoGPT.

* feat: add NanoGPT quota provider option

packages/web/server/lib/quota-providers.js

@@ -200,6 +200,11 @@ export const listConfiguredQuotaProviders = () => {
     configured.add('openrouter');
   }
 
+  const nanopgAuth = normalizeAuthEntry(getAuthEntry(auth, ['nano-gpt', 'nanogpt', 'nano_gpt']));
+  if (nanopgAuth?.key || nanopgAuth?.token) {
+    configured.add('nano-gpt');
+  }
+
   const copilotAuth = normalizeAuthEntry(getAuthEntry(auth, ['github-copilot', 'copilot']));
   if (copilotAuth?.access || copilotAuth?.token) {
     configured.add('github-copilot');
@@ -1195,6 +1200,111 @@ export const fetchZaiQuota = async () => {
   }
 };
 
+const NANO_GPT_DAILY_WINDOW_SECONDS = 86400;
+
+export const fetchNanoGptQuota = async () => {
+  const auth = readAuthFile();
+  const entry = normalizeAuthEntry(getAuthEntry(auth, ['nano-gpt', 'nanogpt', 'nano_gpt']));
+  const apiKey = entry?.key ?? entry?.token;
+
+  if (!apiKey) {
+    return buildResult({
+      providerId: 'nano-gpt',
+      providerName: 'NanoGPT',
+      ok: false,
+      configured: false,
+      error: 'Not configured'
+    });
+  }
+
+  try {
+    const response = await fetch('https://nano-gpt.com/api/subscription/v1/usage', {
+      method: 'GET',
+      headers: {
+        Authorization: `Bearer ${apiKey}`,
+        'Content-Type': 'application/json'
+      }
+    });
+
+    if (!response.ok) {
+      return buildResult({
+        providerId: 'nano-gpt',
+        providerName: 'NanoGPT',
+        ok: false,
+        configured: true,
+        error: `API error: ${response.status}`
+      });
+    }
+
+    const payload = await response.json();
+    const windows = {};
+    const period = payload?.period ?? null;
+    const daily = payload?.daily ?? null;
+    const monthly = payload?.monthly ?? null;
+    const state = payload?.state ?? 'active';
+
+    if (daily) {
+      let usedPercent = null;
+      const percentUsed = daily?.percentUsed;
+      if (typeof percentUsed === 'number') {
+        usedPercent = Math.max(0, Math.min(100, percentUsed * 100));
+      } else {
+        const used = toNumber(daily?.used);
+        const limit = toNumber(daily?.limit ?? daily?.limits?.daily);
+        if (used !== null && limit !== null && limit > 0) {
+          usedPercent = Math.max(0, Math.min(100, (used / limit) * 100));
+        }
+      }
+      const resetAt = toTimestamp(daily?.resetAt);
+      const valueLabel = state !== 'active' ? `(${state})` : null;
+      windows['daily'] = toUsageWindow({
+        usedPercent,
+        windowSeconds: NANO_GPT_DAILY_WINDOW_SECONDS,
+        resetAt,
+        valueLabel
+      });
+    }
+
+    if (monthly) {
+      let usedPercent = null;
+      const percentUsed = monthly?.percentUsed;
+      if (typeof percentUsed === 'number') {
+        usedPercent = Math.max(0, Math.min(100, percentUsed * 100));
+      } else {
+        const used = toNumber(monthly?.used);
+        const limit = toNumber(monthly?.limit ?? monthly?.limits?.monthly);
+        if (used !== null && limit !== null && limit > 0) {
+          usedPercent = Math.max(0, Math.min(100, (used / limit) * 100));
+        }
+      }
+      const resetAt = toTimestamp(monthly?.resetAt ?? period?.currentPeriodEnd);
+      const valueLabel = state !== 'active' ? `(${state})` : null;
+      windows['monthly'] = toUsageWindow({
+        usedPercent,
+        windowSeconds: null,
+        resetAt,
+        valueLabel
+      });
+    }
+
+    return buildResult({
+      providerId: 'nano-gpt',
+      providerName: 'NanoGPT',
+      ok: true,
+      configured: true,
+      usage: { windows }
+    });
+  } catch (error) {
+    return buildResult({
+      providerId: 'nano-gpt',
+      providerName: 'NanoGPT',
+      ok: false,
+      configured: true,
+      error: error instanceof Error ? error.message : 'Request failed'
+    });
+  }
+};
+
 export const fetchQuotaForProvider = async (providerId) => {
   switch (providerId) {
     case 'claude':
@@ -1209,6 +1319,8 @@ export const fetchQuotaForProvider = async (providerId) => {
       return fetchGoogleQuota();
     case 'kimi-for-coding':
       return fetchKimiQuota();
+    case 'nano-gpt':
+      return fetchNanoGptQuota();
     case 'openrouter':
       return fetchOpenRouterQuota();
     case 'zai-coding-plan':