feat(contracts): Route/Render/Theme Manifest 契约 v1 冻结

Co-Authored-By: Claude Code <noreply@anthropic.com>

packages/contracts/src/theme-manifest.ts

@@ -0,0 +1,29 @@
+export const THEME_MANIFEST_VERSION = 1
+
+export interface ThemeManifest {
+  key: string
+  version: string
+  renderContractVersion: string
+  supportedContentTypes: string[]
+  requiredSiteConfig: string[]
+  templates: Array<{ key: string; appliesTo: string }>
+}
+
+const SEMVER = /^\d+\.\d+\.\d+$/
+
+// 守卫查值类型（不只查键存在）：semver 格式、字符串字段、数组元素类型全部校验
+export function isThemeManifest(v: unknown): v is ThemeManifest {
+  if (typeof v !== 'object' || v === null) return false
+  const m = v as ThemeManifest
+  return typeof m.key === 'string'
+    && typeof m.version === 'string' && SEMVER.test(m.version)
+    && typeof m.renderContractVersion === 'string'
+    && Array.isArray(m.supportedContentTypes)
+      && m.supportedContentTypes.every((t) => typeof t === 'string')
+    && Array.isArray(m.requiredSiteConfig)
+      && m.requiredSiteConfig.every((t) => typeof t === 'string')
+    && Array.isArray(m.templates)
+      && m.templates.every((t) => typeof t === 'object' && t !== null
+        && typeof (t as { key: unknown }).key === 'string'
+        && typeof (t as { appliesTo: unknown }).appliesTo === 'string')
+}