fix: memory leak; add: keybindings J and K for file navigation

src/elements.zig

@@ -92,7 +92,17 @@ pub fn Tree(App: type) type {
                     this.scrollback = 0;
                     this.idx = 0;
                 },
-                // TODO also support key inputs to change the current file?
+                .key => |key| {
+                   if (key.eql(.{ .cp = 'J' }) and this.idx < this.len - 1) {
+                       this.idx += 1;
+                       this.queue.push(.{ .file = this.idx });
+                   }
+
+                   if (key.eql(.{ .cp = 'K' }) and this.idx > 0) {
+                       this.idx -= 1;
+                       this.queue.push(.{ .file = this.idx });
+                   }
+                },
                 .mouse => |mouse| if (this.len > 0) switch (mouse.button) {
                     .left => if (mouse.y + this.scrollback < this.len) {
                         this.idx = mouse.y + this.scrollback;