The [x] Done / [ ] Due checkbox v2.0

README.md

@@ -117,6 +117,26 @@ single arrow** (up for ascending, down for descending) when it is ON.
   (which also hides the native sort menu). Per-column state lives in project metadata.
 - **On by default.** Toggle it under "Settings -> Organon Tweaks".
 
+### Done/Due badge
+
+A two-state toggle badge for marking a card done, shown on the board card face (top-right, below the
+header) and on the task view (4th column, near the due date). It reads **`[ ] Due`** (dark red) while
+the task is pending; one click flips it to **`[x] Done`** (light green). The card itself is not
+recolored -- only the badge. The "Due" colors reuse FinanceBuddy's debit badge for consistency.
+
+- Rendered server-side (no JavaScript) via `template:board:private:task:before-title`
+  (`Template/board/done_badge.php`), `template:task:details:fourth-column`
+  (`Template/task/done_badge.php`), and a small head `<style>` (`Template/layout/done_style.php`).
+  Shown only to users who may edit the task; on the board it appears on expanded (non-collapsed) cards.
+- **Single source of truth, no drift with native Close/Open.** With *"Marking Done also closes the
+  task"* **on**, "Done" *means* the task is closed: the badge reads the task's own open/closed status,
+  so closing or reopening a task by any route (the badge, the native sidebar, bulk actions, the API)
+  always keeps the badge correct. A closed "Done" card is hidden from the board by Kanboard's default
+  open-only filter, but reappears if you clear the filter (or use the "Board: show all tasks" filter).
+- With that option **off**, the badge is an independent marker stored in task metadata
+  (`organon_done`) that never touches the open/closed status.
+- **Off by default.** Toggle it under "Settings -> Organon Tweaks".
+
 ## Settings
 
 Global (per Kanboard instance) and admin-only, under "Settings -> Organon Tweaks", grouped as on
@@ -143,6 +163,11 @@ the page:
 
 - **Per-column persistent sort** -- default on.
 
+**Done badge**
+
+- **Show a Done/Due badge on cards** -- default off.
+- **Marking Done also closes the task** -- default off.
+
 Standalone:
 
 - **Keep the board scroll position across refreshes** -- default on.