Astro 7へ更新し、画像をsrc/へ移行・重複を整理

- astro 6→7 / starlight 0.40→0.42 / sharp更新、markdown-remark導入
- markdownをunified()へ移行、compressHTML:trueで従来の空白を維持
- starlight日本語訳パッチを0.42.5向けに再生成
- 有益な画像をsrc/へ移行しpublic重複を削除、孤立画像を整理
- scripts/optimize-images.mjs を追加（prebuildで自動実行）

1 files changed, 7 insertions, 13 deletions

diff --git a/astro.config.mjs b/astro.config.mjs
index 35bdd2a..a3fa95b 100644
--- a/astro.config.mjs
+++ b/astro.config.mjs
@@ -4,6 +4,7 @@ import { fileURLToPath } from "node:url";
 import { defineConfig } from "astro/config";
 import starlight from "@astrojs/starlight";
 import sitemap from "@astrojs/sitemap";
+import { unified } from "@astrojs/markdown-remark";
 import remarkMermaid from "remark-mermaidjs";
 import ogImagePlugin from "./src/plugins/og-image";
 import updatesIntegration from "./src/plugins/updates";
@@ -48,8 +49,13 @@ export default defineConfig({
   site: "https://yasutakeyohei.com",
   base: "/",
   trailingSlash: "always",
+  compressHTML: true,
+  image: {
+    layout: "constrained",
+    responsiveStyles: true,
+  },
   markdown: {
-    remarkPlugins: [remarkMermaid],
+    processor: unified({ remarkPlugins: [remarkMermaid] }),
   },
   vite: {
     plugins: [publicDirIndexPlugin()],
@@ -298,18 +304,6 @@ export default defineConfig({
             },
           ],
         },
-        // The mascot studio is its own section on purpose: it is a personal
-        // hobby project, not one of the site's political-activity tools, and
-        // the ぶるべー character belongs to the city (see the page's opening note).
-        {
-          label: "つくってあそぶ",
-          items: [
-            {
-              label: "ぶるべー スタジオ",
-              link: "/bluebey/",
-            },
-          ],
-        },
         { label: "ご支援", link: "/support/" },
         { label: "コンタクト", link: "/contact/" },
         { label: "私の方針", link: "/policy/" },