Implement the Pico CSS theme editor.

locales/ui/en.ftl

@@ -312,6 +312,16 @@ settings-nav-publishing = Publishing
 settings-nav-data = Data
 settings-nav-mcp = MCP
 settings-nav-style = Style
+style-title = Style
+style-subtitle = Choose the Pico CSS theme used by this project.
+style-themes = Themes
+style-previewMode = Preview Mode
+style-previewMode-auto = Auto
+style-previewMode-light = Light
+style-previewMode-dark = Dark
+style-apply = Apply Theme
+style-applied = Theme applied.
+style-preview = Live Preview
 tags-nav-cloud = Tag Cloud
 tags-nav-manage = Manage Tags
 tags-nav-merge = Merge Tags
@@ -578,7 +588,6 @@ dashboard-timeline = Posts Over Time
 dashboard-recentPosts = Recently Updated
 dashboard-postCount = { $count } posts
 dashboard-pin = Pin
-common-tabNotImplemented = This area will be implemented in a later milestone.
 editor-noPreviewAvailable = No preview available
 common-operationFailed = { $operation } failed: { $error }
 common-databaseUnavailable = Database unavailable