Update comments for the web server (#35366)

The web server is used as minimal mode, whereas public file handling, envs and compression are both handled by the upper layer (edge runtime if deployed serverlessly, or node server if self-hosted).

## Bug

- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Errors have helpful link attached, see `contributing.md`

## Feature

- [ ] Implements an existing feature request or RFC. Make sure the feature request has been accepted for implementation before opening a PR.
- [ ] Related issues linked using `fixes #number`
- [ ] Integration tests added
- [ ] Documentation added
- [ ] Telemetry added. In case of a feature if it's used or not.
- [ ] Errors have helpful link attached, see `contributing.md`

## Documentation / Examples

- [ ] Make sure the linting passes by running `yarn lint`

packages/next/server/web-server.ts

@@ -31,7 +31,8 @@ export default class NextWebServer extends BaseServer {
     }
   }
   protected handleCompression() {
-    // @TODO
+    // For the web server layer, compression is automatically handled by the
+    // upstream proxy (edge runtime or node server) and we can simply skip here.
   }
   protected getRoutesManifest() {
     return {
@@ -49,14 +50,15 @@ export default class NextWebServer extends BaseServer {
     return ''
   }
   protected getPublicDir() {
-    // @TODO
+    // Public files are not handled by the web server.
     return ''
   }
   protected getBuildId() {
     return (globalThis as any).__server_context.buildId
   }
   protected loadEnvConfig() {
-    // @TODO
+    // The web server does not need to load the env config. This is done by the
+    // runtime already.
   }
   protected getHasStaticDir() {
     return false