chore(tooling): track magic by tag and ban hand-built className

.github/workflows/branch-check.yml

@@ -50,7 +50,7 @@ jobs:
   checkup:
     name: 👮 Checkup
     needs: dedupe
-    uses: GSTJ/magic/.github/workflows/ci.yml@main
+    uses: GSTJ/magic/.github/workflows/ci.yml@v1
 
   # Kept out of the shared checkup job: only this one needs a database, and
   # folding it in would spin up Postgres for typecheck/lint/format too. No

apps/nextjs/oxlint.config.mts

@@ -1,9 +1,27 @@
+import { extendConfig } from "magic-oxlint-config";
+import next from "magic-oxlint-config/next";
+
 /**
  * A nested config replaces the root one for everything under `apps/nextjs`, so
- * this file has to be complete on its own. Re-exporting the preset — rather
- * than `defineConfig({ extends: [next] })` — is what makes it complete:
- * `extends` still drops the extended config's `ignorePatterns` on oxlint
- * 1.75.0, so the extends form needs them copied back by hand. The re-export
- * loads the preset as *the* config and every field applies.
+ * this file has to be complete on its own. `extendConfig` flattens the preset
+ * and the additions below into one config, which is what makes it complete:
+ * oxlint's own `extends` still drops the extended config's `ignorePatterns` on
+ * 1.75.0 and needs them re-listed by hand.
+ *
+ * This is the only config in the repo that loads the `magic` jsPlugin.
+ * `magic/no-manual-classname` is a Tailwind rule and Tailwind stops at this
+ * app — the mobile app styles with styled-components and `packages/*` has no
+ * JSX at all, so loading the plugin there would cost startup time to lint
+ * nothing.
  */
-export { default } from "magic-oxlint-config/next";
+export default extendConfig(next, {
+  jsPlugins: [{ name: "magic", specifier: "magic-oxlint-plugin" }],
+
+  rules: {
+    // Class strings go through `cn` (src/lib/utils.ts, `twMerge(clsx(...))`)
+    // or a `cva` variant table. A hand-built one loses the conflict
+    // resolution: `p-2 ${active ? "p-4" : ""}` emits both paddings and leaves
+    // the winner to stylesheet order, where `cn` keeps the last one.
+    "magic/no-manual-classname": "error",
+  },
+});

package.json

@@ -31,6 +31,7 @@
     "magic-codemods": "^1.1.0",
     "magic-oxfmt-config": "^1.2.0",
     "magic-oxlint-config": "^1.2.0",
+    "magic-oxlint-plugin": "^1.1.0",
     "magic-tsconfig": "^1.2.0",
     "oxfmt": "0.60.0",
     "oxlint": "1.75.0",

pnpm-workspace.yaml

@@ -64,6 +64,7 @@ minimumReleaseAgeExclude:
   - magic-oxfmt-config@1.2.0
   - magic-oxlint-config@1.2.0
   - magic-tsconfig@1.2.0
+  - magic-oxlint-plugin@1.1.0
 
 # pnpm 10+ does not run dependency install scripts unless they are listed here,
 # and pnpm 11 makes an unanswered list a hard install failure. Every entry ran