Refactoring: move all code files into a src directory

src/UI/Base/SubtleButton.svelte

@@ -0,0 +1,31 @@
+<script lang="ts">
+  import { createEventDispatcher } from "svelte"
+  import BaseUIElement from "../BaseUIElement"
+  import Img from "./Img"
+  import { twJoin, twMerge } from "tailwind-merge"
+
+  export let imageUrl: string | BaseUIElement = undefined
+  export const message: string | BaseUIElement = undefined
+  export let options: {
+    imgSize?: string
+    extraClasses?: string
+  } = {}
+
+  let imgClasses = twJoin("block justify-center shrink-0 mr-4", options?.imgSize ?? "h-11 w-11")
+  const dispatch = createEventDispatcher<{ click }>()
+</script>
+
+<button
+  class={twMerge(options.extraClasses, "secondary no-image-background")}
+  on:click={(e) => dispatch("click", e)}
+>
+  <slot name="image">
+    {#if imageUrl !== undefined}
+      {#if typeof imageUrl === "string"}
+        <Img src={imageUrl} class={imgClasses} />
+      {/if}
+    {/if}
+  </slot>
+
+  <slot name="message" />
+</button>