chore: clean up repo for public release

- Remove BMAD framework, IDE configs, dev screenshots, test files,
  internal docs, and backup files
- Rename keep-notes/ to memento-note/
- Update all references from keep-notes to memento-note
- Add Apache 2.0 license with Commons Clause (non-commercial restriction)
- Add clean .gitignore and .env.docker.example

memento-note/lib/theme-script.ts

@@ -0,0 +1,31 @@
+export function getThemeScript(theme: string = 'light') {
+  return `
+    (function() {
+      try {
+        var localTheme = localStorage.getItem('theme-preference');
+        var theme = localTheme || '${theme}';
+        var root = document.documentElement;
+        
+        root.classList.remove('dark');
+        root.removeAttribute('data-theme');
+
+        if (theme === 'auto') {
+          if (window.matchMedia('(prefers-color-scheme: dark)').matches) {
+            root.classList.add('dark');
+          }
+        } else if (theme === 'dark') {
+          root.classList.add('dark');
+        } else if (theme === 'light') {
+          // do nothing
+        } else {
+          root.setAttribute('data-theme', theme);
+          if (theme === 'midnight') {
+            root.classList.add('dark');
+          }
+        }
+      } catch (e) {
+        console.error('Theme script error', e);
+      }
+    })();
+  `
+}