feat: show customer branding on login page

Adds public /v1/store/branding and /v1/store/logo endpoints so the
login page can display the customer's name and logo without auth,
with "Powered by LunarFront" underneath — matching the sidebar style.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

packages/backend/src/routes/v1/store.ts

@@ -1,9 +1,43 @@
 import type { FastifyPluginAsync } from 'fastify'
 import { eq } from 'drizzle-orm'
 import { companies, locations } from '../../db/schema/stores.js'
+import { files } from '../../db/schema/files.js'
 import { ValidationError } from '../../lib/errors.js'
 
 export const storeRoutes: FastifyPluginAsync = async (app) => {
+  // --- Public branding (no auth — used on login page) ---
+
+  app.get('/store/branding', async (_request, reply) => {
+    const [store] = await app.db.select({
+      name: companies.name,
+      logoFileId: companies.logoFileId,
+    }).from(companies).limit(1)
+    if (!store) return reply.send({ name: null, hasLogo: false })
+    return reply.send({ name: store.name, hasLogo: !!store.logoFileId })
+  })
+
+  app.get('/store/logo', async (_request, reply) => {
+    const [store] = await app.db.select({ logoFileId: companies.logoFileId }).from(companies).limit(1)
+    if (!store?.logoFileId) return reply.status(404).send({ error: { message: 'No logo configured', statusCode: 404 } })
+
+    const [file] = await app.db.select().from(files).where(eq(files.id, store.logoFileId)).limit(1)
+    if (!file) return reply.status(404).send({ error: { message: 'Logo file not found', statusCode: 404 } })
+
+    try {
+      const data = await app.storage.get(file.path)
+      const ext = file.path.split('.').pop()?.toLowerCase()
+      const contentTypeMap: Record<string, string> = {
+        jpg: 'image/jpeg', jpeg: 'image/jpeg', png: 'image/png', webp: 'image/webp', svg: 'image/svg+xml',
+      }
+      return reply
+        .header('Content-Type', contentTypeMap[ext ?? ''] ?? 'application/octet-stream')
+        .header('Cache-Control', 'public, max-age=3600')
+        .send(data)
+    } catch {
+      return reply.status(404).send({ error: { message: 'Logo file not readable', statusCode: 404 } })
+    }
+  })
+
   // --- Company / Store Settings ---
 
   app.get('/store', { preHandler: [app.authenticate, app.requirePermission('settings.view')] }, async (request, reply) => {