Clean up code. Reorganize files. Port stuff from other branches. + more

This turns the project into a monorepo using pnpm workspaces,
dramatically simplifying the build process. It also fixes a lot of bugs
and just generally makes the codebase a lot cleaner.

packages/widget/vite.config.ts

@@ -17,13 +17,10 @@ export default defineConfig({
                 dir: 'dist',
             },
         },
-        // WARN: this setting has caused issues for me in the past, but now it
-        // seems to work fine. I'm not sure why, but minifying the bundle saves
-        // 5KB, and it doesnt *cause* issues, so I'm leaving it on.
-        minify: true,
+        minify: true
     },
 
     plugins: [
-        dts(),
+        dts()
     ],
 });