Address code review feedback and add workflow permissions

Co-authored-by: bartlomieju <13602871+bartlomieju@users.noreply.github.com>

Author: Copilot

.github/workflows/issue_pr_insights.yml

@@ -13,6 +13,8 @@ on:
 jobs:
   insights:
     runs-on: ubuntu-latest
+    permissions:
+      contents: read
     steps:
       - name: Checkout
         uses: actions/checkout@v6

tools/issue_pr_insights.ts

@@ -40,6 +40,7 @@ interface GitHubItem {
   html_url: string;
   created_at: string;
   comments: number;
+  pull_request?: unknown;
 }
 
 async function getLastRunTimestamp(): Promise<string | null> {
@@ -237,10 +238,7 @@ async function main() {
   ]);
 
   // Filter out pull requests from the issues endpoint results
-  const newIssues = allIssueItems.filter(
-    // deno-lint-ignore no-explicit-any
-    (item: any) => !item.pull_request,
-  );
+  const newIssues = allIssueItems.filter((item) => !item.pull_request);
   const newPRs = allPRs;
 
   const noResponseIssues = newIssues.filter((i) => i.comments === 0);