feat: Implement secure static file serving with path traversal protection and XSS prevention for template titles.

src/web/router.test.ts

@@ -19,6 +19,31 @@ describe("Web Router", () => {
         expect(data).toHaveProperty("status", "ok");
     });
 
+    it("should block path traversal", async () => {
+        // Attempts to go up two directories to reach the project root or src
+        const req = new Request("http://localhost/public/../../package.json");
+        const res = await router(req);
+        // Should be 403 Forbidden or 404 Not Found (our logical change makes it 403)
+        expect([403, 404]).toContain(res.status);
+    });
+
+    it("should serve existing static file", async () => {
+        // We know style.css exists in src/web/public
+        const req = new Request("http://localhost/public/style.css");
+        const res = await router(req);
+        expect(res.status).toBe(200);
+        if (res.status === 200) {
+            const text = await res.text();
+            expect(text).toContain("body");
+        }
+    });
+
+    it("should not serve static files on non-GET methods", async () => {
+        const req = new Request("http://localhost/public/style.css", { method: "POST" });
+        const res = await router(req);
+        expect(res.status).toBe(404);
+    });
+
     it("should return 404 for unknown routes", async () => {
         const req = new Request("http://localhost/unknown");
         const res = await router(req);