fix(tools): freeze the tool id array handed out by getToolIds

`getToolIds()` returned the module's internal array by reference, so a caller
doing `getToolIds().sort()` would reorder it in place and silently corrupt every
later lookup — the in-place-mutation footgun `.claude/rules/sim-react-performance.md`
calls out.

Frozen rather than copied: the array is consumed in loops, so copying would
allocate on every call. Freezing makes the mutation throw instead of corrupt, and
`[...getToolIds()].sort()` still works. Return type is now `readonly string[]`,
so the mistake is a compile error rather than a runtime surprise.

No caller mutates it today; this is closing the hole, not fixing a live bug.

Author: waleedlatif1

apps/sim/tools/tool-ids.ts

@@ -14,7 +14,13 @@ import rawToolIds from '@/tools/generated/tool-ids'
  * including returning the input unchanged when nothing matches. See
  * `.agents/skills/tool-registry-boundary/SKILL.md`.
  */
-const toolIds: string[] = rawToolIds
+/**
+ * Frozen because {@link getToolIds} hands it out directly. Returning a copy
+ * would allocate on every call in the loops that consume it; freezing makes an
+ * in-place `sort()`/`push()` by a caller throw rather than silently corrupt
+ * every later lookup.
+ */
+const toolIds: readonly string[] = Object.freeze(rawToolIds)
 
 const toolIdSet = new Set(toolIds)
 
@@ -48,8 +54,8 @@ function getLatestByBaseName(): Map<string, string> {
   return latestByBaseName
 }
 
-/** Every registered tool id, including versioned variants. */
-export function getToolIds(): string[] {
+/** Every registered tool id, including versioned variants. Frozen — copy before sorting. */
+export function getToolIds(): readonly string[] {
   return toolIds
 }