feat(web): complete MVP0 public layout, banner, and SEO baseline

packages/db/src/settings.ts

@@ -1,6 +1,20 @@
 import { db } from "./client"
 
 const ADMIN_SELF_REGISTRATION_KEY = "admin.self_registration_enabled"
+const PUBLIC_HEADER_BANNER_KEY = "public.header_banner"
+
+type PublicHeaderBannerRecord = {
+  enabled: boolean
+  message: string
+  ctaLabel?: string
+  ctaHref?: string
+}
+
+export type PublicHeaderBanner = {
+  message: string
+  ctaLabel?: string
+  ctaHref?: string
+}
 
 function resolveEnvFallback(): boolean {
   return process.env.CMS_ADMIN_SELF_REGISTRATION_ENABLED === "true"
@@ -18,6 +32,25 @@ function parseStoredBoolean(value: string): boolean | null {
   return null
 }
 
+function parsePublicHeaderBanner(value: string): PublicHeaderBannerRecord | null {
+  try {
+    const parsed = JSON.parse(value) as Record<string, unknown>
+
+    if (typeof parsed.enabled !== "boolean" || typeof parsed.message !== "string") {
+      return null
+    }
+
+    return {
+      enabled: parsed.enabled,
+      message: parsed.message,
+      ctaLabel: typeof parsed.ctaLabel === "string" ? parsed.ctaLabel : undefined,
+      ctaHref: typeof parsed.ctaHref === "string" ? parsed.ctaHref : undefined,
+    }
+  } catch {
+    return null
+  }
+}
+
 export async function isAdminSelfRegistrationEnabled(): Promise<boolean> {
   try {
     const setting = await db.systemSetting.findUnique({
@@ -54,3 +87,30 @@ export async function setAdminSelfRegistrationEnabled(enabled: boolean): Promise
     },
   })
 }
+
+export async function getPublicHeaderBanner(): Promise<PublicHeaderBanner | null> {
+  try {
+    const setting = await db.systemSetting.findUnique({
+      where: { key: PUBLIC_HEADER_BANNER_KEY },
+      select: { value: true },
+    })
+
+    if (!setting) {
+      return null
+    }
+
+    const parsed = parsePublicHeaderBanner(setting.value)
+
+    if (!parsed || !parsed.enabled) {
+      return null
+    }
+
+    return {
+      message: parsed.message,
+      ctaLabel: parsed.ctaLabel,
+      ctaHref: parsed.ctaHref,
+    }
+  } catch {
+    return null
+  }
+}