chore: bootstrap CHFS NG workspace

compatibility/api-v1.md

@@ -0,0 +1,17 @@
+# CHFS v1 compatibility surface
+
+Keep legacy endpoints stable during migration.
+
+- session: login/logout
+- files: directory listing
+- shared: direct file access
+- newdir: create directory
+- rename: rename file/directory
+- rmfiles: delete
+- search: global search
+- upload/upload2: upload
+- newtext/updatetext: text file editing
+- preview: preview
+- exist: existence check
+- downloaddir: ZIP directory download
+- webdav: WebDAV