fix(dashboard): preserve combo success percentage scale (#11595)

Merged via /merge-batch (lote 2026-08-26, v3.8.51). Boarded no worktree combinado junto com outras ~30 PRs; validação única: typecheck/complexity/cognitive-complexity/changelog-integrity verdes, file-size rebaseado onde necessário (crescimento legítimo), lint com os mesmos 228 achados pré-existentes confirmados via sonda contra o tip puro (não introduzidos por este lote), e ~370 testes focados (unit + vitest) passando. Obrigado pela contribuição.

changelog.d/fixes/11595-combo-success-rate-scale.md

@@ -0,0 +1 @@
+- **fix(dashboard):** Provider Stats now displays combo success rates on their native 0–100 percentage scale instead of multiplying them twice ([#11595](https://github.com/diegosouzapw/OmniRoute/pull/11595)) — thanks @pacocartones

src/app/(dashboard)/dashboard/provider-stats/page.tsx

@@ -9,8 +9,10 @@
 
 import { useState, useEffect, useCallback, Fragment } from "react";
 import { useTranslations } from "next-intl";
-import { Card } from "@/shared/components";
+
 import { useProviderNodeMap, resolveProviderName } from "@/lib/display/useProviderNodeMap";
+import { formatComboSuccessRate } from "@/lib/usage/providerStatsFormatters";
+import { Card } from "@/shared/components";
 
 interface ProviderStat {
   provider: string;
@@ -493,7 +495,7 @@ export default function ProviderStatsPage() {
                     </td>
                     <td className="py-2 px-3 text-right tabular-nums">
                       {typeof m.successRate === "number"
-                        ? `${(m.successRate * 100).toFixed(1)}%`
+                        ? formatComboSuccessRate(m.successRate)
                         : "—"}
                     </td>
                   </tr>

src/lib/usage/providerStatsFormatters.ts

@@ -0,0 +1,3 @@
+export function formatComboSuccessRate(successRatePercent: number): string {
+  return `${successRatePercent.toFixed(1)}%`;
+}

tests/unit/provider-stats-formatters.test.ts

@@ -0,0 +1,38 @@
+import assert from "node:assert/strict";
+import fs from "node:fs";
+import path from "node:path";
+import test from "node:test";
+
+import {
+  getComboMetrics,
+  recordComboRequest,
+  resetAllComboMetrics,
+} from "../../open-sse/services/comboMetrics.ts";
+import { formatComboSuccessRate } from "../../src/lib/usage/providerStatsFormatters.ts";
+
+test.after(resetAllComboMetrics);
+
+test("formatComboSuccessRate preserves the producer's 0-100 percentage scale", () => {
+  resetAllComboMetrics();
+  recordComboRequest("format-test", "openai/gpt-4o-mini", {
+    success: true,
+    latencyMs: 10,
+  });
+
+  const metrics = getComboMetrics("format-test");
+  assert.ok(metrics);
+  assert.equal(metrics.successRate, 100);
+  assert.equal(formatComboSuccessRate(metrics.successRate), "100.0%");
+  assert.equal(formatComboSuccessRate(50), "50.0%");
+  assert.equal(formatComboSuccessRate(0), "0.0%");
+});
+
+test("Provider Stats renders combo metrics through the percentage-scale formatter", () => {
+  const source = fs.readFileSync(
+    path.resolve("src/app/(dashboard)/dashboard/provider-stats/page.tsx"),
+    "utf8"
+  );
+
+  assert.match(source, /formatComboSuccessRate\(m\.successRate\)/);
+  assert.doesNotMatch(source, /m\.successRate\s*\*\s*100/);
+});