Update coding standards guidance and add publishers helper foundation

.github/copilot-instructions.md

@@ -33,7 +33,8 @@ This is a crowdfunding platform for games with a developer theme. The applicatio
 - Make sure all guidance in the Copilot Instructions file is updated with any relevant changes, including to project structure and scripts, and programming guidance
 
 ### Code formatting requirements
-
+- Every exported function should have a TSDoc comment describing its purpose, parameters, and return value.
+- Before imports or any code, add a comment block to the file that explains its purpose.
 - Use TypeScript with explicit types for function parameters and return values, especially in the data layer (`db/`, `src/lib/`)
 - Frontend code (TypeScript, Astro) must pass ESLint checks (`npm run lint`)
 

src/lib/publishers.ts

@@ -0,0 +1,31 @@
+/**
+ * Data-access helpers for publisher summary records used by Astro pages.
+ */
+
+import { asc } from 'drizzle-orm';
+import type { Database } from './db';
+import { publishers } from '../../db/schema';
+import type { Publisher } from '../types/game';
+
+type PublisherSummaryRow = {
+    id: number;
+    name: string;
+};
+
+/**
+ * Returns all publishers ordered by name.
+ *
+ * @param db - Drizzle database client.
+ * @returns A list of publisher summaries including only `id` and `name`.
+ */
+export async function getAllPublishers(db: Database): Promise<Publisher[]> {
+    const rows = await db
+        .select({ id: publishers.id, name: publishers.name })
+        .from(publishers)
+        .orderBy(asc(publishers.name));
+
+    return rows.map((row: PublisherSummaryRow) => ({
+        id: row.id,
+        name: row.name,
+    }));
+}