feat: add monthly quota to API response body

Add monthlyQuotaRemaining/monthlyQuotaLimit fields to QRResponseDto
populated from X-Quota-* headers set by rate limiter. MCP server
now displays quota in tool result text instead of web credits.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Controllers/QRManagerController.cs

@@ -114,6 +114,14 @@ namespace QRRapidoApp.Controllers
                 };
             }
 
+            // Inject monthly quota from response headers (set by ApiKeyAuthorizeAttribute)
+            if (HttpContext.Response.Headers.TryGetValue("X-Quota-Remaining", out var qr) &&
+                int.TryParse(qr, out var quotaRemaining))
+                result.MonthlyQuotaRemaining = quotaRemaining;
+            if (HttpContext.Response.Headers.TryGetValue("X-Quota-Limit", out var ql) &&
+                int.TryParse(ql, out var quotaLimit))
+                result.MonthlyQuotaLimit = quotaLimit;
+
             // Map format and mimeType into the response
             result.Format   = format;
             result.MimeType = format switch

Models/DTOs/QRResponseDto.cs

@@ -18,5 +18,11 @@ namespace QRRapidoApp.Models.DTOs
 
         /// <summary>MIME type of the encoded image (e.g. "image/png", "image/webp").</summary>
         public string MimeType { get; set; } = "image/png";
+
+        /// <summary>Monthly API quota remaining (from rate limiter). -1 = unlimited.</summary>
+        public int MonthlyQuotaRemaining { get; set; } = -1;
+
+        /// <summary>Monthly API quota limit. -1 = unlimited.</summary>
+        public int MonthlyQuotaLimit { get; set; } = -1;
     }
 }

mcp-server/index.mjs

@@ -109,7 +109,9 @@ function successContent(data, label = "qr") {
           file ? `🖼  Aberto em: ${file}` : "",
           `⏱  ${data.generationTimeMs}ms`,
           `💾 Cache: ${data.fromCache ? "hit" : "miss"}`,
-          `📊 Créditos restantes: ${data.remainingCredits ?? "N/A"}`
+          data.monthlyQuotaLimit >= 0
+            ? `📊 Quota mensal: ${data.monthlyQuotaRemaining}/${data.monthlyQuotaLimit}`
+            : `📊 Quota mensal: ilimitada`
         ].filter(Boolean).join("\n")
       }
     ]

mcp-server/server-http.mjs

@@ -164,7 +164,7 @@ function createMcpServer(apiKey) {
       return {
         content: [
           { type: "image", data: data.qrCodeBase64, mimeType: data.mimeType || "image/png" },
-          { type: "text", text: `✅ QR gerado (${type})\n⏱ ${data.generationTimeMs}ms\n💾 cache: ${data.fromCache ? "hit" : "miss"}` }
+          { type: "text", text: `✅ QR gerado (${type})\n⏱ ${data.generationTimeMs}ms\n💾 cache: ${data.fromCache ? "hit" : "miss"}\n📊 quota: ${data.monthlyQuotaRemaining >= 0 ? `${data.monthlyQuotaRemaining}/${data.monthlyQuotaLimit}` : "ilimitada"}` }
         ]
       };
     }