ci: validate decision document metadata

package.json

@@ -77,8 +77,9 @@
   },
   "scripts": {
     "prepublishOnly": "bun run check && bun run test",
-    "check": "bun run check:config-contract && bun run check:discipline && bun run format:check && bun run lint && bun run typecheck",
+    "check": "bun run check:config-contract && bun run check:docs-contract && bun run check:discipline && bun run format:check && bun run lint && bun run typecheck",
     "check:config-contract": "node scripts/check-config-contract.mjs",
+    "check:docs-contract": "node scripts/check-docs-contract.mjs",
     "check:discipline": "node scripts/check-discipline-ledger.mjs",
     "prepare": "node scripts/prepare-effect-tsgo.mjs",
     "format": "biome format --write .",

scripts/check-docs-contract.mjs

@@ -0,0 +1,60 @@
+import { readdirSync, readFileSync } from "node:fs";
+import { join, relative, resolve } from "node:path";
+
+const root = resolve("docs");
+const requiredDecisionFields = [
+  "decision-status",
+  "created",
+  "last-reviewed",
+  "applies-to",
+  "owner",
+  "related-issues",
+  "related-prs",
+  "supersedes",
+];
+
+function markdownFiles(directory) {
+  return readdirSync(directory, { withFileTypes: true }).flatMap((entry) => {
+    const path = join(directory, entry.name);
+    if (entry.isDirectory()) return markdownFiles(path);
+    return entry.isFile() && entry.name.endsWith(".md") ? [path] : [];
+  });
+}
+
+function frontmatter(text) {
+  const match = text.match(/^---\n([\s\S]*?)\n---\n/);
+  if (!match) return null;
+  return new Map(
+    match[1]
+      .split("\n")
+      .map((line) => line.match(/^([\w-]+):\s*(.*)$/))
+      .filter(Boolean)
+      .map(([, key, value]) => [key, value.trim()]),
+  );
+}
+
+const files = markdownFiles(root);
+const decisions = files.filter(
+  (file) =>
+    file.includes(`${join("docs", "decisions")}${"/"}`) &&
+    !["README.md", "TEMPLATE.md"].includes(file.split("/").pop()),
+);
+const errors = [];
+
+for (const file of decisions) {
+  const metadata = frontmatter(readFileSync(file, "utf8"));
+  if (!metadata) {
+    errors.push(`${relative(process.cwd(), file)}: missing YAML frontmatter`);
+    continue;
+  }
+  for (const field of requiredDecisionFields) {
+    if (!metadata.get(field)) errors.push(`${relative(process.cwd(), file)}: missing ${field}`);
+  }
+}
+
+if (errors.length) {
+  console.error(errors.join("\n"));
+  process.exit(1);
+}
+
+console.log(`docs contract (${decisions.length} decision records)`);