fix: keep getColorFromString finite for long strings (#651)

lib/utils/getColorFromString.ts

@@ -1,7 +1,22 @@
 export const getColorFromString = (string: string, alpha = 1) => {
   // pseudo random number from string
-  const hash = string.split("").reduce((acc, char) => {
-    return acc * 31 + char.charCodeAt(0)
-  }, 0)
-  return `hsl(${hash % 360}, 100%, 50%, ${alpha})`
+  //
+  // `acc * 31 + code` grows without bound: it leaves exact-integer range at
+  // 11 characters and overflows to Infinity past ~200, at which point
+  // `Infinity % 360` is NaN and the result is an unparseable `hsl(NaN, ...)`.
+  // Net ids here are selector paths such as
+  // `group > capacitor.C101 > port.pin1 to U100.VOUT`, so deeply nested
+  // groups reach that length in practice.
+  //
+  // Keeping the accumulator in signed 32-bit range via `| 0` is the standard
+  // string-hash formulation and stays finite and exact for any input.
+  let hash = 0
+  for (let i = 0; i < string.length; i++) {
+    hash = (hash * 31 + string.charCodeAt(i)) | 0
+  }
+
+  // `%` keeps the sign of the dividend, so normalise into [0, 360).
+  const hue = ((hash % 360) + 360) % 360
+
+  return `hsl(${hue}, 100%, 50%, ${alpha})`
 }