feat:find and watch location, use shadcn sonner toast for errors.

- added tailwindcss with shadcn-svelte sonner toasts
- added a location store and a geolation util to find, watch, use and
store locations and their updates
- added a LocationButton to navigate to the current location and handle
errors.
- updated the Map to use LocationButton and go to current location.

src/lib/components/sonner/index.ts

@@ -0,0 +1 @@
+export { default as Toaster } from "./sonner.svelte";

src/lib/components/sonner/sonner.svelte

@@ -0,0 +1,30 @@
+<script lang="ts">
+	import { Toaster as Sonner, type ToasterProps as SonnerProps } from 'svelte-sonner';
+	import { mode } from 'mode-watcher';
+
+	let { ...restProps }: SonnerProps = $props();
+</script>
+
+<Sonner
+	theme={mode.current}
+	class="toaster group"
+	style="--normal-bg: var(--color-popover); --normal-text: var(--color-popover-foreground); --normal-border: var(--color-border);"
+	{...restProps}
+/>
+
+<style>
+	:global([data-sonner-toast][data-type='error']) {
+		background-color: #fef2f2 !important;
+		border-color: #ef4444 !important;
+		color: #dc2626 !important;
+	}
+
+	:global([data-sonner-toast][data-type='error'] [data-icon]) {
+		color: #ef4444 !important;
+	}
+
+	:global([data-sonner-toast][data-type='error'] [data-content]) {
+		color: #dc2626 !important;
+		font-weight: 500;
+	}
+</style>