Upgrade to Astro 5, apply bincio design system, fix mdast-util-from-markdown v2 compat

- Bump astro@5, @astrojs/mdx@4, @astrojs/rss@4, @astrojs/sitemap@3
- Add @astrojs/tailwind, @astrojs/svelte, tailwindcss, svelte
- Add patch-package + patches for mdast-util-wikirefs and mdast-util-caml
  to fix getData/setData → this.data.key and this.exit() return value for
  mdast-util-from-markdown v2 API compatibility
- Fix wikirefs.ts resolveEmbedContent signature for new 3-arg call
- Fix backrefs.ts: guard wikirefs.scan() against non-iterable return
- Add Base.astro layout with bincio dark/light theme tokens, nav, Inter font
- Replace global.css with bincio CSS variables + wiki-specific prose styles
- Update Entry.astro, BlogPost.astro, index.astro, map.astro, blog/index.astro
  to use Base.astro layout with Tailwind utility classes
- Add tailwind.config.mjs (Inter + JetBrains Mono, zinc palette)
- Update SITE_TITLE to BincioWiki, site URL to wiki.bincio.com

astro.config.mjs

@@ -1,44 +1,35 @@
-import { base, defineConfig } from 'astro/config';
+import { defineConfig } from 'astro/config';
 import sitemap from '@astrojs/sitemap';
+import tailwind from '@astrojs/tailwind';
+import svelte from '@astrojs/svelte';
 import { remarkWikiRefs } from 'remark-wikirefs';
 import { remarkCaml } from 'remark-caml';
-
 import {
-	resolveHtmlHref,
-	resolveHtmlText,
-	createResolveEmbedContent,
-	generateForeRefsRemarkPlugin,
+  resolveHtmlHref,
+  resolveHtmlText,
+  createResolveEmbedContent,
+  generateForeRefsRemarkPlugin,
 } from './src/wikibonsai/wikirefs';
 
-
 const remarkPlugins = [
-	remarkCaml,
-	[
-		remarkWikiRefs,
-		{
-			resolveHtmlHref: resolveHtmlHref,
-			resolveHtmlText: resolveHtmlText,
-			resolveEmbedContent: null, // we'll set this later -- see below
-		},
-	],
-	generateForeRefsRemarkPlugin,
+  remarkCaml,
+  [
+    remarkWikiRefs,
+    {
+      resolveHtmlHref,
+      resolveHtmlText,
+      resolveEmbedContent: null,
+    },
+  ],
+  generateForeRefsRemarkPlugin,
 ];
 
-// embed content needs access to a unified processor
 const resolveEmbedContent = createResolveEmbedContent(remarkPlugins);
 remarkPlugins[1][1].resolveEmbedContent = resolveEmbedContent;
 
-// https://astro.build/config
 export default defineConfig({
-	site: 'https://astro-bloomz.netlify.app',
-	integrations: [
-		sitemap(),
-	],
-	assetsInclude: true,
-	markdown: {
-		// Preserve Astro's default plugins: GitHub-flavored Markdown and Smartypants
-		extendDefaultPlugins: true,
-		// Applied to .md and .mdx files
-		remarkPlugins: remarkPlugins,
-	},
+  site: 'https://wiki.bincio.com',
+  integrations: [sitemap(), tailwind(), svelte()],
+  legacy: { collections: true },
+  markdown: { remarkPlugins },
 });