plugins/dap-python: require dap to be explicitly enabled

Instead of automatically enabling `plugins.dap`, require users to
explicitly enable it. This prevents silent re-enabling of dap when
a user has explicitly disabled it.

plugins/by-name/dap-python/default.nix

@@ -1,4 +1,5 @@
 {
+  config,
   lib,
   pkgs,
   ...
@@ -76,10 +77,14 @@ lib.nixvim.plugins.mkNeovimPlugin {
   # Manually supplied to nvim-dap config module
   callSetup = false;
   extraConfig = cfg: {
-    plugins.dap = {
-      enable = true;
+    assertions = lib.nixvim.mkAssertions "plugins.dap-python" {
+      assertion = config.plugins.dap.enable;
+      message = ''
+        You have to enable `plugins.dap` to use `plugins.dap-python`.
+      '';
+    };
 
-      extensionConfigLua = ''
+    plugins.dap.extensionConfigLua = ''
       require("dap-python").setup("${cfg.adapterPythonPath}", ${toLuaObject cfg.settings})
     ''
     + (optionalString (cfg.testRunners != null) ''
@@ -96,7 +101,6 @@ lib.nixvim.plugins.mkNeovimPlugin {
       require("dap-python").test_runner = ${toLuaObject cfg.testRunner};
     '');
   };
-  };
 
   # NOTE: Renames added in https://github.com/nix-community/nixvim/pull/2897 (2025-01-26)
   imports = [ ./deprecations.nix ];

tests/test-sources/plugins/by-name/dap-python/default.nix

@@ -1,9 +1,11 @@
 {
   empty = {
+    plugins.dap.enable = true;
     plugins.dap-python.enable = true;
   };
 
   example = {
+    plugins.dap.enable = true;
     plugins.dap-python = {
       enable = true;
 
@@ -34,6 +36,7 @@
   };
 
   default = {
+    plugins.dap.enable = true;
     plugins.dap-python = {
       enable = true;