Initial commit: two Clojure Android todo apps

Side-by-side comparison of viable Clojure-on-Android approaches:
- todo-expo/: ClojureScript + shadow-cljs + Expo + Reagent + re-frame
- todo-flutter/: ClojureDart + Flutter

Both apps feature: add/remove/check-off todos, SQLite persistence,
categories, priorities, edit support, swipe-to-delete, filtering.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

todo-expo/etc/metro-bundler.patch

@@ -0,0 +1,12 @@
+--- worker.js    2018-11-21 14:46:01.271844624 -0700
++++ worker.js    2018-11-21 14:45:52.517615272 -0700
+@@ -218,7 +218,7 @@
+     }
+
+     if (!options.transformOptions.dev) {
+-      plugins.push([constantFoldingPlugin, opts]);
++      // plugins.push([constantFoldingPlugin, opts]);
+       plugins.push([inlinePlugin, opts]);
+     }var _transformFromAstSync = transformFromAstSync(ast, "", {
+         ast: true,
+         babelrc: false,