fix(core): check only for watcher connections during inactivity shutdown (#29621)

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## Current Behavior
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We currently second guess our inactivity timer by checking if there are
any open connections. However, there's also a strong chance that plugin
workers will remain open as long as the daemon is open. This means the
daemon stays alive forever and the daemon never shuts down even though
it is inactive.

## Expected Behavior
<!-- This is the behavior we should expect with the changes in this PR
-->

Instead of checking for open connections in general, the daemon server
will only check for open file watchers. Most Daemon client requests will
restart the server when sending messages so we can safely shut the
server down in most cases. The only case where shutting down the daemon
would cause a disruption is if a file watcher is registered. In those
cases, the daemon will not shutdown due to inactivity.

## Related Issue(s)
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merged. -->

Fixes #

(cherry picked from commit 32a2ca8)

Author: FrozenPandaz

packages/nx/src/daemon/server/server.ts

@@ -17,6 +17,7 @@ import {
   killSocketOrPath,
 } from '../socket-utils';
 import {
+  hasRegisteredFileWatcherSockets,
   registeredFileWatcherSockets,
   removeRegisteredFileWatcherSocket,
 } from './file-watching/file-watcher-sockets';
@@ -311,9 +312,9 @@ export async function handleResult(
 }
 
 function handleInactivityTimeout() {
-  if (numberOfOpenConnections > 0) {
+  if (hasRegisteredFileWatcherSockets()) {
     serverLogger.log(
-      `There are ${numberOfOpenConnections} open connections. Reset inactivity timer.`
+      `There are open file watchers. Resetting inactivity timer.`
     );
     resetInactivityTimeout(handleInactivityTimeout);
   } else {