On CDP client disconnect, terminate Env

Protects against a stuck worker. This works even if the worker isn't currently
in JS but then enters JS.

src/cdp/CDP.zig

@@ -168,6 +168,12 @@ pub fn onLinkDisconnect(self: *CDP, err: ?anyerror) void {
     self.browser.http_client.inbox.push(arena, .{ .disconnect = err });
 }
 
+// Called by Network to try to force the Worker to shutdown. Protects against a
+// stuck worker.
+pub fn terminateFromNetwork(self: *CDP) void {
+    self.browser.env.terminate();
+}
+
 // Called in the Worker to dispatch a single CDP message bubbled up by
 // HttpClient.drainInbox. The Network thread already parsed the JSON
 // when it pushed the message to the inbox, so we skip straight to

src/network/Network.zig

@@ -536,6 +536,8 @@ fn dropCdp(self: *Network, link: *CdpLink, err: ?anyerror, notify: bool) void {
     link.state = .removed;
     self.cdp_dirty = true;
     if (notify) {
+        link.cdp.terminateFromNetwork();
+
         // notify=true means the worker hasn't been told yet — push the
         // disconnect into the inbox and break it out of curl_multi_poll.
         // notify=false paths have already woken the worker (close frame