⚡ Bolt: Optimize handle ID generation

.Jules/bolt.md

@@ -1,3 +1,6 @@
 ## 2025-06-27 - [Map Initialization Overhead]
 **Learning:** Initializing Maps with `new Map(array.map(...))` creates unnecessary intermediate arrays, consuming memory and triggering garbage collection overhead, especially noticeable when dealing with many nodes.
 **Action:** Use a `for...of` loop to directly `map.set()` elements rather than creating an intermediate array of tuples, especially in frequently executed or rendering paths.
+## 2024-07-20 - String Iteration Performance
+**Learning:** For high-frequency string operations in the frontend (e.g., generating handle IDs for nodes/edges), avoid using `Array.from(string)` as it creates intermediate array allocations and increases garbage collection overhead.
+**Action:** Use a `for...of` loop or standard string iteration to avoid intermediate allocations and reduce garbage collection pressure.

frontend/src/erd/handleUtils.ts

@@ -1,8 +1,16 @@
 export function sanitizeHandleId(columnName: string): string {
-  const encoded = Array.from(columnName, (char) => {
-    // Array.from only yields non-empty Unicode scalars, so codePointAt(0) is defined.
-    return char.codePointAt(0)!.toString(16).padStart(4, '0')
-  }).join('-')
+  // Optimize string generation to avoid intermediate array allocations
+  // from Array.from and .join('-') by using a direct string builder.
+  let encoded = ''
+  let isFirst = true
+  for (const char of columnName) {
+    if (isFirst) {
+      isFirst = false
+    } else {
+      encoded += '-'
+    }
+    encoded += char.codePointAt(0)!.toString(16).padStart(4, '0')
+  }
 
   return `c-${encoded || 'empty'}`
 }