web: data-driven switcher & save mode switcher

also:
- disabled ssr to enable localstorage
- removed the workaround for hover, as it looks bad

web/src/components/buttons/SettingsContextButton.svelte

@@ -0,0 +1,32 @@
+<script
+    lang="ts"
+    generics="
+        Context extends Exclude<keyof CobaltSettings, 'schemaVersion'>,
+        Id extends keyof CobaltSettings[Context],
+        Key extends CobaltSettings[Context][Id]
+    "
+>
+    import settings, { updateSetting } from "$lib/settings";
+    import type { CobaltSettings } from "$lib/types/settings";
+
+    export let settingContext: Context;
+    export let settingId: Id;
+    export let settingKey: Key;
+
+    $: setting = $settings[settingContext][settingId];
+    $: isSelected = setting === settingKey;
+</script>
+
+<button
+    id="setting-button-{settingContext}-{String(settingId)}-{settingKey}"
+    class="button"
+    class:selected={isSelected}
+    on:click={() =>
+        updateSetting({
+            [settingContext]: {
+                [settingId]: settingKey,
+            },
+        })}
+>
+    <slot></slot>
+</button>