feat: add ability to configure the agent (also theme switcher) (#3)

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Reviewed-on: #3
Co-authored-by: Naomi Carrigan <commits@nhcarrigan.com>
Co-committed-by: Naomi Carrigan <commits@nhcarrigan.com>

src/app.css

@@ -1,9 +1,11 @@
 @import "tailwindcss";
 
-:root {
+:root,
+[data-theme="dark"] {
   --bg-primary: #1a1a2e;
   --bg-secondary: #16213e;
   --bg-terminal: #0f0f1a;
+  --bg-hover: #2a2a4a;
   --accent-primary: #e94560;
   --accent-secondary: #ff6b9d;
   --text-primary: #ffffff;
@@ -11,6 +13,18 @@
   --border-color: #2a2a4a;
 }
 
+[data-theme="light"] {
+  --bg-primary: #f8f9fa;
+  --bg-secondary: #ffffff;
+  --bg-terminal: #f1f3f4;
+  --bg-hover: #e8e8e8;
+  --accent-primary: #e94560;
+  --accent-secondary: #ff6b9d;
+  --text-primary: #1a1a2e;
+  --text-secondary: #5a5a7a;
+  --border-color: #d0d0e0;
+}
+
 html,
 body {
   margin: 0;