fix: guard CAST(val AS BIGINT) against Infinity from toNumber()

CAST('infinity' AS BIGINT) would call BigInt(Math.trunc(Infinity))
which throws RangeError. toNumber() can return Infinity for extreme
bigint→number conversions or parseFloat("infinity"). Added
Number.isFinite guard, returning 0n for non-finite values.

Author: teamchong

src/sql/evaluator.ts

@@ -219,7 +219,8 @@ function castValue(val: unknown, targetType: string): unknown {
   if (t === "bigint") {
     if (typeof val === "bigint") return val;
     if (typeof val === "string") { try { return BigInt(val); } catch { return 0n; } }
-    return BigInt(Math.trunc(toNumber(val)));
+    const n = toNumber(val);
+    return Number.isFinite(n) ? BigInt(Math.trunc(n)) : 0n;
   }
   if (t === "int" || t === "integer") return Math.trunc(toNumber(val));
   if (t === "float" || t === "double" || t === "real" || t === "decimal" || t === "numeric") return toNumber(val);