Add live Markdown editing, colours and files in the tree

README.md

@@ -274,8 +274,8 @@ in the blame gutter, using each author's chosen colour either way.
 ## Desktop Client
 
 `Client/` is SaraView as a desktop app, built with Flet and laid out like
-SaraFem: a directory tree on the left, the file list on the right, and an
-open file in place of the list. It has two modes, picked in Settings >
+SaraFem: a tree of directories and files on the left, the file list on the
+right, and an open file in place of the list. It has two modes, picked in Settings >
 Connection:
 
 - **Local**: browses one root directory on your own computer (any path).
@@ -288,8 +288,12 @@ Connection:
   locks are enforced by the server as usual, and SaraTag tags show above
   the file. Download saves a file, or a directory as a .zip.
 
-Markdown is rendered in View, config and HTML files are highlighted, and
-Edit/Save (Ctrl+E, Ctrl+S) work like the web view. Images show in the app;
+Config and HTML files are highlighted, and Edit/Save (Ctrl+E, Ctrl+S) work
+like the web view. Markdown follows the "Markdown editing" setting (also in
+the web view's settings): **Live** shows it rendered and lets you edit
+in place, like Obsidian (click a heading to see and edit its `#`s; Esc puts
+it back), with Source (Ctrl+E) for the plain text; **Separate** keeps View
+and Edit as two modes. Images show in the app;
 videos and other files open in their default program (Open Externally).
 
 Rename takes a `/` to move, like the web view (`../Archive/Notes.md`).