test(hooks): remove unsafe test assertions

Ultraworked with [Sisyphus](https://github.com/code-yeongyu/oh-my-openagent)

Co-authored-by: Sisyphus <clio-agent@sisyphuslabs.ai>

src/hooks/comment-checker/cli.test.ts

@@ -74,7 +74,7 @@ done
       const originalSetTimeout = globalThis.setTimeout
       globalThis.setTimeout = ((fn: (...args: unknown[]) => void, _ms?: number) => {
         fn()
-        return 0 as unknown as ReturnType<typeof setTimeout>
+        return testCoerce<ReturnType<typeof setTimeout>>(0)
       }) as typeof setTimeout
 
       try {
@@ -102,7 +102,7 @@ done
       const originalSetTimeout = globalThis.setTimeout
       globalThis.setTimeout = ((fn: (...args: unknown[]) => void, _ms?: number) => {
         fn()
-        return 0 as unknown as ReturnType<typeof setTimeout>
+        return testCoerce<ReturnType<typeof setTimeout>>(0)
       }) as typeof setTimeout
 
       try {

src/hooks/comment-checker/pending-calls.test.ts

@@ -7,18 +7,18 @@ describe("pending-calls cleanup interval", () => {
     const setIntervalCalls: number[] = []
     let unrefCalled = 0
 
-    globalThis.setInterval = ((
+    globalThis.setInterval = testCoerce<typeof setInterval>(((
       _handler: TimerHandler,
       timeout?: number,
-      ..._args: any[]
+      ..._args: unknown[]
     ) => {
       setIntervalCalls.push(timeout as number)
-      return {
+      return testCoerce<ReturnType<typeof setInterval>>({
         unref: () => {
           unrefCalled += 1
         },
-      } as unknown as ReturnType<typeof setInterval>
-    }) as unknown as typeof setInterval
+      })
+    }))
 
     try {
       const modulePath = new URL("./pending-calls.ts", import.meta.url).pathname
@@ -43,20 +43,20 @@ describe("pending-calls cleanup interval", () => {
     let intervalHandle: ReturnType<typeof setInterval> | undefined
     let clearCalls = 0
 
-    globalThis.setInterval = ((
+    globalThis.setInterval = testCoerce<typeof setInterval>(((
       _handler: TimerHandler,
       _timeout?: number,
-      ..._args: any[]
+      ..._args: unknown[]
     ) => {
-      intervalHandle = { unref: () => {} } as unknown as ReturnType<typeof setInterval>
+      intervalHandle = testCoerce<ReturnType<typeof setInterval>>({ unref: () => {} })
       return intervalHandle
-    }) as unknown as typeof setInterval
+    }))
 
-    globalThis.clearInterval = ((handle?: ReturnType<typeof setInterval>) => {
+    globalThis.clearInterval = testCoerce<typeof clearInterval>(((handle?: ReturnType<typeof setInterval>) => {
       if (handle === intervalHandle) {
         clearCalls += 1
       }
-    }) as unknown as typeof clearInterval
+    }))
 
     try {
       const modulePath = new URL("./pending-calls.ts", import.meta.url).pathname