treewide: consolidate iconsPackage removal and warning

plugins/deprecation.nix

@@ -14,6 +14,21 @@ let
     # Added 2024-09-17
     surround = "vim-surround";
   };
+  # Added 2024-09-21; remove after 24.11
+  # `iconsPackage` options were briefly available in the following plugins for ~3 weeks
+  iconsPackagePlugins = [
+    "telescope"
+    "lspsaga"
+    "nvim-tree"
+    "neo-tree"
+    "trouble"
+    "alpha"
+    "diffview"
+    "fzf-lua"
+    "bufferline"
+    "barbar"
+    "chadtree"
+  ];
 in
 {
 
@@ -36,5 +51,36 @@ in
           "plugins"
           new
         ]
-    ) renamed);
+    ) renamed)
+    ++ builtins.map (
+      name:
+      lib.mkRemovedOptionModule
+        [
+          "plugins"
+          name
+          "iconsPackage"
+        ]
+        ''
+          Please use `plugins.web-devicons` or `plugins.mini.modules.icons` with `plugins.mini.mockDevIcons` instead.
+        ''
+    ) iconsPackagePlugins
+    # Show a warning when web-devicons is auto-enabled
+    ++ [
+      (
+        { config, options, ... }:
+        {
+          config = lib.mkIf (options.plugins.web-devicons.enable.highestPrio == 1490) {
+            warnings = [
+              ''
+                Nixvim: `plugins.web-devicons` was enabled automatically because the following plugins are enabled.
+                This behaviour is deprecated. Please explicitly define `plugins.web-devicons.enable` or alternatively enable `plugins.mini.modules.icons` with `plugins.mini.mockDevIcons`.
+                ${lib.concatMapStringsSep "\n" (name: "plugins.${name}") (
+                  builtins.filter (name: config.plugins.${name}.enable) iconsPackagePlugins
+                )}
+              ''
+            ];
+          };
+        }
+      )
+    ];
 }