feat: add Gemini CLI theme templates

GEMINI.md

@@ -77,5 +77,6 @@ Apex is not about pretty colors; it is about signal clarity.
 │ ├── zed/
 │ ├── zsh/
 │ ├── kitty/
+│ ├── gemini/
 │ └── alacritty/
 └── dist/ # Compiled theme files (gitignore this)

templates/gemini/apex.json.j2

@@ -0,0 +1,24 @@
+{
+  "name": "{{ scheme }}",
+  "type": "custom",
+  "Background": "{{ palette.background }}",
+  "Foreground": "{{ palette.foreground }}",
+  "LightBlue": "{{ ansi.bright.blue }}",
+  "AccentBlue": "{{ palette.info }}",
+  "AccentPurple": "{{ palette.special }}",
+  "AccentCyan": "{{ ansi.bright.cyan }}",
+  "AccentGreen": "{{ palette.success }}",
+  "AccentYellow": "{{ palette.warning }}",
+  "AccentRed": "{{ palette.cursor }}",
+  "Comment": "{{ ui.dim }}",
+  "Gray": "{{ ui.stealth }}",
+  "DiffAdded": "{{ palette.success }}",
+  "DiffRemoved": "{{ palette.error }}",
+  "DiffModified": "{{ palette.warning }}",
+  "text": {
+    "primary": "{{ palette.foreground }}",
+    "secondary": "{{ ui.dim }}",
+    "accent": "{{ palette.info }}",
+    "response": "{{ palette.foreground }}"
+  }
+}