fix(loop-detector): test now validates old loops are ignored

Create actual loop pattern (3 identical calls) in oldHistory to properly
test that loops outside the recent history window are not detected.
Uses varied tools in filler to avoid triggering alternating pattern.

Addresses cubic-dev-ai review on PR code-yeongyu#1188

Author: agno01

src/hooks/loop-detector/index.test.ts

@@ -92,22 +92,26 @@ describe("loop-detector", () => {
 
     test("only considers recent history window", () => {
       //#given
-      const oldHistory: ToolCallRecord[] = Array.from({ length: 20 }, (_, i) => ({
-        tool: "read",
-        args: { path: `/old-${i}.ts` },
-        timestamp: i,
-      }))
-      const recentHistory: ToolCallRecord[] = [
-        { tool: "read", args: { path: "/new.ts" }, timestamp: 21 },
-        { tool: "edit", args: { path: "/new.ts" }, timestamp: 22 },
+      // Create a loop pattern in old history (3 identical calls = would trigger detection)
+      const loopInOldHistory: ToolCallRecord[] = [
+        { tool: "read", args: { path: "/looped.ts" }, timestamp: 1 },
+        { tool: "read", args: { path: "/looped.ts" }, timestamp: 2 },
+        { tool: "read", args: { path: "/looped.ts" }, timestamp: 3 },
       ]
-      const history = [...oldHistory, ...recentHistory]
+      // Add enough unique calls (varied tools) to push the loop outside the history window
+      const tools = ["glob", "grep", "bash", "write", "lsp_diagnostics"]
+      const fillerHistory: ToolCallRecord[] = Array.from({ length: 12 }, (_, i) => ({
+        tool: tools[i % tools.length],
+        args: { path: `/filler-${i}.ts` },
+        timestamp: 10 + i,
+      }))
+      const history = [...loopInOldHistory, ...fillerHistory]
 
       //#when
       const result = detectLoop(history)
 
       //#then
-      // Should not detect loop from old repeated reads
+      // Loop in old history (outside window) should be ignored
       expect(result).toBeNull()
     })
   })