Stack Window

The main application window that displays the task stack and provides keyboard- and mouse-driven editing.

Requirements

The window MUST be hidden on startup and shown only when triggered by the hotkey or the tray "Open Stack" menu item.
The window MUST be a topmost window that appears above other application windows.
Closing the window MUST hide it rather than quit the application.
The window MUST have a minimum size of 320x160 pixels.
The window SHOULD persist its size and position across launches via the settings.

The window MUST support a light theme and a dark theme.
The application SHOULD detect the operating system's color scheme preference at startup and whenever it changes.
On Windows, the application SHOULD watch for live theme changes and react immediately.
On macOS and Linux, the application SHOULD periodically poll the OS theme preference.
The window MUST apply the active theme to all UI elements: background, text, entry field, canvas, description panel, drag handles, and selection highlight.

The window MUST use font family and font size values from the application settings.
The default font size MUST be 11.

The window MUST display a text entry field at the top for adding new tasks.
Pressing Enter in the entry field MUST add the task to the top of the stack (push) and clear the field.
Pressing Shift+Enter in the entry field MUST add the task as the next item (position 1) and clear the field.
Pressing Home in the entry field MUST add the task to the top of the stack (push) and clear the field.
Pressing End in the entry field MUST add the task to the bottom of the active list (push_last) and clear the field.
Pressing Escape while the entry is focused during editing MUST cancel the edit and return focus to the task list.

The window MUST render tasks as rows, with the current task (position 0) displayed in bold.
Each row MUST display: a drag handle, the task index, a status indicator, the task text, a started-at timestamp, a last-current timestamp, and a duration.
Rows for tasks that have a description MUST display a note indicator next to the task text.
The current task (position 0) MUST show a fire status indicator.
Non-current tasks MUST show a sleep status indicator.
Every task row MUST display started_at as the first timestamp column and last_current as the second timestamp column.
The duration for the current task MUST update live every second.
Timestamp and duration column widths MUST adapt to the configured font.
When the stack is empty, the window MUST display "No tasks — type above and press Enter".

When a task is selected, a description panel MUST be shown below the task list.
The description panel MUST contain an editable multi-line text area.
If the selected task has a description, the panel MUST display it. Otherwise, the panel MUST display a placeholder prompt.
The placeholder MUST be cleared when the description area receives focus.
The description MUST be saved automatically when the description area loses focus.
The description MUST be saved when Escape is pressed in the description area, and focus MUST return to the task list.
The description panel MUST be hidden when no task is selected.

Digit keys (0-9, including numpad) MUST save any pending description edit, select the corresponding row by index, and refresh the description panel.
Up/Down arrow keys MUST save any pending description edit, move the selection up or down by one row, and refresh the description panel.
Left/Right arrow keys with a row selected MUST reorder that row by one position.
The Home key with a row selected MUST promote that row to the top of the stack.
The End key with a row selected MUST send that row to the bottom of the stack.
Backspace/Delete with a row selected MUST remove (soft-delete) that task. After deletion, the selection SHOULD move to the nearest remaining row.
The ? key MUST open a keyboard shortcuts help dialog.
Escape MUST hide the window (or close the help dialog if open).
Enter/Return with a row selected MUST begin editing that task's text in the entry field.
Pressing Enter while editing MUST save the updated text. Pressing Escape MUST cancel.
Typing a printable character while the task list is focused MUST redirect focus to the entry field and begin typing.

The application MUST provide a help dialog listing all available keyboard shortcuts.
The help dialog MUST be openable via the ? key and via the tray menu.
The help dialog SHOULD be positioned relative to the main window if visible, otherwise centered on screen.
Pressing Escape or ? inside the help dialog MUST close it.

The window MUST support mouse drag-and-drop to reorder tasks.
Initiating a drag MUST save any pending description edit.
Dragging a row MUST immediately reorder the stack and persist the change.
Releasing a drag on the same row where it started (no movement) MUST select that row.

The window MUST reload tasks from disk, clear the selection, hide the description panel, cancel any in-progress edit, and redraw whenever refreshed.
The window SHOULD notify the tray and coordinator whenever the stack changes.