Add tests for plugin activation with --force flag

Add comprehensive tests to verify that plugins remain activated when
using --force with --activate or --activate-network flags. These tests
cover both single-site and multisite scenarios.

Co-authored-by: swissspidy <841956+swissspidy@users.noreply.github.com>

Author: Copilot

features/plugin-install.feature

@@ -338,3 +338,36 @@ Feature: Install WordPress plugins
       """
       active
       """
+
+  Scenario: Force update a network-active plugin with --activate-network flag should keep it network-activated
+    Given a WP multisite install
+
+    When I run `wp plugin install hello-dolly --activate-network`
+    Then STDOUT should contain:
+      """
+      Plugin 'hello-dolly' network activated.
+      """
+    And the return code should be 0
+
+    When I run `wp plugin list --name=hello-dolly --field=status`
+    Then STDOUT should be:
+      """
+      active-network
+      """
+
+    When I run `wp plugin install hello-dolly --force --activate-network`
+    Then STDOUT should contain:
+      """
+      Plugin updated successfully
+      """
+    And STDOUT should contain:
+      """
+      Success: Installed 1 of 1 plugins.
+      """
+    And the return code should be 0
+
+    When I run `wp plugin list --name=hello-dolly --field=status`
+    Then STDOUT should be:
+      """
+      active-network
+      """

src/Plugin_Command.php

@@ -378,7 +378,9 @@ public function activate( $args, $assoc_args = [] ) {
 				continue;
 			}
 			// Network-active is the highest level of activation status.
-			if ( 'active-network' === $status ) {
+			// However, when called from install command (chained_command), always attempt activation
+			// to handle edge cases where the plugin may have been deactivated during the install process.
+			if ( 'active-network' === $status && ! $this->chained_command ) {
 				WP_CLI::warning( "Plugin '{$plugin->name}' is already network active." );
 				continue;
 			}