Aligns the baseline of +project and @context chips with due:/rec: chips
which already render Tabler SVG prefixes. Without an icon the text-only
prefix sat a few pixels off vertically.
The DaisyUI <details>/<summary> dropdown didn't toggle reliably in Firefox
(summary + inline-flex badge), and :focus-within left the wrong row open
when TransitionGroup reordered tasks on sort. Replace with a Vue-controlled
ref + onClickOutside, render options as colored badge buttons (no menu
hover underline), and lift the widget by z-index: 1 only while open so the
absolute menu paints above the next row.
Replace the markdown _todo/todo.md view with a structured todo.txt UI at the
repo root: priority dropdown, inline body edit, project/context/due/rec chips
with Tabler icons, add input as a join-suffix, project/context filter columns
with TransitionGroup animation, priority-sorted list. Drops the now-unused
.todo-notes markdown checkbox styles from app.css.
