feat(modules): add cosmic-edit text editor module

Add COSMIC Text Editor (cosmic-edit) configuration module with the following
settings:

- Theme configuration (Dark/Light/System)
- Editor preferences (auto-indent, tab width, word wrap)
- Font customization (name and size)
- Search options (case sensitivity, regex, wrap around)
- Vim bindings support
- Syntax highlighting themes

Also includes directory restructure from 'apps' to 'applications' for better
naming clarity.

modules/all-modules.nix

@@ -1,7 +1,7 @@
 { lib, ... }:
 let
   appletsByName = ./applets/by-name;
-  appsByName = ./apps/by-name;
+  applicationsByName = ./applications/by-name;
   misc = ./misc;
 in
 [
@@ -15,8 +15,8 @@ in
 ]
 ++ lib.foldlAttrs (
   prev: name: type:
-  prev ++ lib.optional (type == "directory") (appsByName + "/${name}")
-) [ ] (builtins.readDir appsByName)
+  prev ++ lib.optional (type == "directory") (applicationsByName + "/${name}")
+) [ ] (builtins.readDir applicationsByName)
 ++ lib.foldlAttrs (
   prev: name: type:
   prev ++ lib.optional (type == "directory") (appletsByName + "/${name}")

modules/applications/by-name/cosmic-edit/default.nix

@@ -0,0 +1,97 @@
+{ lib, ... }:
+lib.cosmic.applications.mkCosmicApplication {
+  name = "cosmic-edit";
+  originalName = "COSMIC Text Editor";
+  identifier = "com.system76.CosmicEdit";
+  configurationVersion = 1;
+
+  maintainers = [ lib.maintainers.HeitorAugustoLN ];
+
+  settingsOptions =
+    let
+      inherit (lib.cosmic) defaultNullOpts;
+    in
+    {
+      app_theme =
+        defaultNullOpts.mkRonEnum [ "Dark" "Light" "System" ]
+          {
+            __type = "enum";
+            variant = "System";
+          }
+          ''
+            The theme of the application.
+          '';
+
+      auto_indent = defaultNullOpts.mkBool true ''
+        Whether to automatically indent the code.
+      '';
+
+      find_case_sensitive = defaultNullOpts.mkBool false ''
+        Whether to make the search case sensitive.
+      '';
+
+      find_use_regex = defaultNullOpts.mkBool false ''
+        Whether to use regular expressions in the search.
+      '';
+
+      find_wrap_around = defaultNullOpts.mkBool true ''
+        Whether to wrap around the search.
+      '';
+
+      font_name = defaultNullOpts.mkStr "Fira Mono" ''
+        The name of the font to be used.
+      '';
+
+      font_size = defaultNullOpts.mkU16 14 ''
+        The size of the font to be used.
+      '';
+
+      highlight_current_line = defaultNullOpts.mkBool true ''
+        Whether to highlight the current line.
+      '';
+
+      line_numbers = defaultNullOpts.mkBool true ''
+        Whether to show line numbers.
+      '';
+
+      syntax_theme_dark = defaultNullOpts.mkStr "COSMIC Dark" ''
+        The name of the dark syntax theme to be used.
+      '';
+
+      syntax_theme_light = defaultNullOpts.mkStr "COSMIC Light" ''
+        The name of the light syntax theme to be used.
+      '';
+
+      tab_width = defaultNullOpts.mkU16 4 ''
+        The width of the tab.
+      '';
+
+      vim_bindings = defaultNullOpts.mkBool false ''
+        Whether to enable Vim bindings.
+      '';
+
+      word_wrap = defaultNullOpts.mkBool true ''
+        Whether to wrap the words.
+      '';
+    };
+
+  settingsExample = {
+    app_theme = {
+      __type = "enum";
+      variant = "System";
+    };
+    auto_indent = true;
+    find_case_sensitive = false;
+    find_use_regex = false;
+    find_wrap_around = true;
+    font_name = "Fira Mono";
+    font_size = 16;
+    highlight_current_line = true;
+    line_numbers = true;
+    syntax_theme_dark = "COSMIC Dark";
+    syntax_theme_light = "COSMIC Light";
+    tab_width = 2;
+    vim_bindings = true;
+    word_wrap = true;
+  };
+}