Migrate ESLint to @hasparus/eslint-config (flat config, ESLint 10) (#115)

* Migrate ESLint to @hasparus/eslint-config (flat config, ESLint 10)

- replace inlined @edgeandnode .eslintrc.cjs with flat eslint.config.js
- extend @hasparus/eslint-config/the-guild; disable perfectionist/sort-*
  and unicorn/prefer-global-this
- astro block lints frontmatter (projectService off; astro parser can't
  drive type-aware linting)
- solid + check-file + better-tailwindcss blocks
- pnpm override pins @typescript-eslint/* to 8.62.1: @theguild/eslint-config
  drags in utils@8.26 which crashes on ESLint 10

* Use @hasparus/eslint-config astro + solid presets

Thin consumer config: [...astro, ...solid] + per-repo tailwind entrypoint
and check-file. Drops direct astro-parser/solid/better-tailwindcss/compat
deps (now transitive via presets). Aligns @typescript-eslint override to
8.61.1 to match the shared config.

* Green up lint: rename .ts→.tsx, fix errors, pin 2.3.0

- rename 18 src .ts → .tsx (check-file .tsx-only convention)
- fix genuine errors: no-empty-function (noop), innerText→textContent,
  no-array-reduce→loop, no-await-expression-member, prefer-top-level-await,
  no-explicit-any→MarkdownInstance, prefer-add-event-listener (+ latent
  removeEventListener bug), a11y backdrop-dismiss (intent-disabled)
- add DOM.Iterable to tsconfig lib (NodeList spread/.at were untyped)
- disable low-value unicorn/consistent-function-scoping; suppress
  astro no-undef + solid react/display-name false positives
- pin @hasparus/eslint-config to exact 2.3.0

Remaining: 7 solid/reactivity + 1 no-console warnings (non-blocking).

* Patch prettier-plugin-astro to not crash on unformattable <style>

- pnpm patch: embedStyle falls back to raw <style> when the CSS parser
  throws, instead of aborting the whole file (upstream withastro/
  prettier-plugin-astro#459)
- fix malformed empty-selector rule in PostLayout <style>

* Bump @hasparus/eslint-config to 2.3.1; drop consumer suppressions

no-undef(astro) + react/display-name(solid) now live in the presets.

* Bump @hasparus/eslint-config to 3.0.0; drop @typescript-eslint override

3.0.0 dropped @TheGuild, so the @typescript-eslint/utils@8.26 dedup override
is no longer needed. Uses /astro + /solid (unaffected by the /the-guild removal).

* Address review nits: execFileSync, leaner error log, MDXInstance type

- derivedTitleAndDatePlugin: execSync shell string -> execFileSync arg array
- Image.astro: log available image keys, not the whole glob map
- [...path].astro: MDXInstance (not MarkdownInstance) for the .mdx glob

Author: hasparus

.eslintignore

@@ -0,0 +1,29 @@
+import astro from "@hasparus/eslint-config/astro";
+import solid from "@hasparus/eslint-config/solid";
+import checkFile from "eslint-plugin-check-file";
+
+export default [
+  { ignores: ["**/*.mdx", "**/*.md", "**/*.gitignored.*"] },
+
+  ...astro,
+  ...solid,
+
+  {
+    settings: {
+      "better-tailwindcss": { entryPoint: "src/global-styles/base.css" },
+    },
+  },
+
+  {
+    rules: { "unicorn/consistent-function-scoping": "off" },
+  },
+
+  {
+    files: ["src/**/*.ts"],
+    ignores: ["**/*.d.ts", "**/*.xml.ts", "**/*.txt.ts", "**/*.md.ts"],
+    plugins: { "check-file": checkFile },
+    rules: {
+      "check-file/filename-blocklist": ["error", { "**/*.ts": "*.tsx" }],
+    },
+  },
+];

.eslintrc.cjs

@@ -35,8 +35,6 @@
     "@types/unist": "^3.0.3",
     "@vercel/og": "^0.6.2",
     "astro": "^6.4.6",
-    "astro-eslint-parser": "^1.4.0",
-    "eslint-plugin-markdown": "^5.0.0",
     "estree-util-value-to-estree": "^3.5.0",
     "gray-matter": "4.0.3",
     "plaiceholder": "^3.0.0",
@@ -55,12 +53,13 @@
   },
   "devDependencies": {
     "@astrojs/rss": "^4.0.18",
-    "@edgeandnode/eslint-config": "^2.0.3",
+    "@hasparus/eslint-config": "3.0.0",
     "@playwright/test": "1.60.0",
     "@types/hast": "3.0.4",
     "@types/node": "^22.0.0",
     "cssnano": "^7.1.5",
-    "eslint": "^8.57.0",
+    "eslint": "^10.6.0",
+    "eslint-plugin-check-file": "3.3.1",
     "prettier": "^3.8.3",
     "prettier-plugin-astro": "^0.14.0",
     "prettier-plugin-tailwindcss": "^0.8.0",
@@ -83,6 +82,9 @@
       "core-js-pure",
       "puppeteer",
       "sharp"
-    ]
+    ],
+    "patchedDependencies": {
+      "prettier-plugin-astro@0.14.0": "patches/prettier-plugin-astro@0.14.0.patch"
+    }
   }
 }

eslint.config.js

@@ -0,0 +1,30 @@
+diff --git a/dist/index.js b/dist/index.js
+index 6b9f37eac7baa92be5d3a7d6e6054886f99dcac4..817f3c7381c67dfe07f5de53228c161c6e12e963 100644
+--- a/dist/index.js
++++ b/dist/index.js
+@@ -747,10 +747,21 @@ async function embedStyle(lang, content, path, print, textToDoc, options) {
+         case 'less':
+         case 'css':
+         case 'scss': {
+-            let formattedStyles = await wrapParserTryCatch(textToDoc, content, {
+-                ...options,
+-                parser: lang,
+-            });
++            let formattedStyles;
++            try {
++                formattedStyles = await textToDoc(content, {
++                    ...options,
++                    parser: lang,
++                });
++            }
++            catch {
++                const node = path.getNode();
++                return node
++                    ? Buffer.from(options.originalText)
++                        .subarray(options.locStart(node), options.locEnd(node))
++                        .toString()
++                    : undefined;
++            }
+             formattedStyles = stripTrailingHardline(formattedStyles);
+             const attributes = path.map(print, 'attributes');
+             const openingTag = group(['<style', indent(group(attributes)), softline, '>']);