feat(discovery): expose recommendation confidence and reason codes

Author: DaviRain-Su

apps/dashboard/index.html

@@ -3353,12 +3353,15 @@ <h3>Action Console</h3>
           const data = await res.json().catch(() => ({ ok: false }));
           if (!res.ok || data?.ok === false) throw new Error(data?.error || `discover failed (${res.status})`);
           const recommended = data?.data?.recommended || "";
+          const confidence = String(data?.data?.confidence || "none");
+          const reasonCode = String(data?.data?.reasonCode || "unknown");
+          const source = String(data?.data?.source || "unknown");
           const top = (data?.data?.candidates || []).slice(0, 3).map((x) => `${x.pool} (liq=${Number(x.liquidityScore || 0).toFixed(2)})`);
           if (recommended) {
             bscConfigPoolEl.value = recommended;
-            metaEl.textContent = `Auto-discover ${protocol}: selected ${recommended}`;
+            metaEl.textContent = `Auto-discover ${protocol}: selected ${recommended} [source=${source}, confidence=${confidence}]`;
           } else {
-            metaEl.textContent = `Auto-discover ${protocol}: no candidate found. ${data?.data?.warning || ""}`;
+            metaEl.textContent = `Auto-discover ${protocol}: withheld/no candidate [reason=${reasonCode}, source=${source}] ${data?.data?.warning || ""}`;
           }
           if (bscConfigCardEl && top.length) {
             bscConfigCardEl.innerHTML += `<br/>discovered top: <span class="muted">${top.join(" ; ")}</span>`;

apps/dashboard/server.mjs

@@ -9496,13 +9496,31 @@ async function discoverBscPoolsByProtocol(protocol) {
 	const rows = await scorePoolCandidates(candidates);
 	const topScore = Number(rows[0]?.liquidityScore || 0);
 	const recommended = topScore > 0 ? (rows[0]?.pool ?? null) : null;
+	let reasonCode = "recommended";
 	if (!warning && rows.length > 0 && topScore <= 0) {
 		warning =
 			"auto-discovery candidates found but liquidity score is zero; recommendation withheld for safety";
+		reasonCode = "withheld_zero_liquidity";
 	}
+	if (rows.length === 0) {
+		reasonCode = "no_candidates";
+	}
+	if (!recommended && rows.length > 0 && topScore > 0) {
+		reasonCode = "withheld_policy";
+	}
+	const confidence =
+		recommended && topScore > 1_000
+			? "high"
+			: recommended && topScore > 50
+				? "medium"
+				: recommended
+					? "low"
+					: "none";
 	return {
 		protocol: key,
 		source,
+		reasonCode,
+		confidence,
 		candidates: rows,
 		recommended,
 		warning,