feat: advance local-first workspace checklist

- add admin access-policy UI and local access control surfaces

- add local markdown conflict resolution UI and smoke coverage

- add ACP local agent changed-files audit scaffold and read-only write guard

- document current P0-P2 checklist progress and verification evidence

rust/crates/mnote-web/src/ssr/pages/home.rs

@@ -24,6 +24,9 @@ pub fn HomePage(
     /// 当前选中的页面标题（可选）
     #[prop(optional)]
     active_page_title: Option<String>,
+    /// 是否显示管理员授权入口
+    #[prop(optional)]
+    show_admin_access_policy: bool,
 ) -> impl IntoView {
     let active_page_id = active_page_id.unwrap_or_default();
     let active_page_title = active_page_title
@@ -40,7 +43,7 @@ pub fn HomePage(
         .map(|workspace_id| format!("/documents/{active_page_id}?workspaceId={workspace_id}"))
         .unwrap_or_else(|| format!("/documents/{active_page_id}"));
     view! {
-        <PageLayout current_nav="home" sidebar_tree_html={sidebar_tree_html.unwrap_or_default()} workspace_name={workspace_name.unwrap_or_default()} workspace_sidebar_html={workspace_sidebar_html.unwrap_or_default()} topbar_title={active_page_title.clone()}>
+        <PageLayout current_nav="home" sidebar_tree_html={sidebar_tree_html.unwrap_or_default()} workspace_name={workspace_name.unwrap_or_default()} workspace_sidebar_html={workspace_sidebar_html.unwrap_or_default()} topbar_title={active_page_title.clone()} show_admin_access_policy={show_admin_access_policy}>
             {move || if has_active_page {
                 view! {
                     <main class="document-shell document-shell--workspace-entry" data-root-active-page-id={active_page_id.clone()} data-editor-host="leptos_tiptap_island">
@@ -61,7 +64,19 @@ pub fn HomePage(
                 view! {
                     <section class="mnote-workspace-empty-state" data-testid="mnote-workspace-empty-state">
                         <h1>"暂无页面"</h1>
-                        <p>"当前工作区还没有可显示的页面。"</p>
+                        <p>"当前还没有可显示的本地工作区。"</p>
+                        <button
+                            type="button"
+                            class="mnote-empty-create-page"
+                            data-testid="mnote-create-default-local-workspace"
+                            data-mnote-action="create-local-workspace"
+                        >"创建我的空间"</button>
+                        <button
+                            type="button"
+                            class="mnote-empty-create-page"
+                            data-testid="mnote-open-local-folder-empty"
+                            data-mnote-action="open-local-folder"
+                        >"打开本地文件夹"</button>
                         <button
                             type="button"
                             class="mnote-empty-create-page"