Highlight current card: wash the cursor's card faintly in its status color

[davidbudac]

What

A new Appearance setting, Highlight current card (highlight_current_card, on by default).

The card under the cursor on the grid trades its gray sel_bg fill for a very faint wash of the color its frame would wear unselected:

• red: needs feedback
• yellow: running
• blue: finished and unread

While something is going on, the wash breathes slowly (~1.6 s, on the existing sweep clock). A quiet card or a terminal card gets a still accent wash, and so does every card with Animations off.

The wash stays lit while you type in the card's pane, so you can see which card you're working on. It fades further while the project tabs hold the keys.

Off keeps today's gray fill, unchanged.

Screenshots

Rendered from the real card-drawing code with the default theme. The terminal palette is approximated with xterm's defaults.

Off vs on (you're typing in the running card's pane):

Each state, setting on:

Breathing:

How

• launcher_view.rs: selected_card_block takes the card's status color (card_edge). card_tint picks the color and level. dim_toward_black / color_rgb scale ANSI/256 colors to truecolor, as focus_tint already is.
• The setting follows the usual path: SettingKind + SettingSpec, a Config field, an App mirror, apply_config, and a row in docs/configuration.md.
• Tests: config default/toggle/persist, and the wash's color, breathing, still, animations-off and project-tabs cases.

Notes

• Levels: TINT_FLOOR 0.07, TINT_PEAK 0.20, TINT_STILL 0.13.
• event_loop::tests::question_mark_ignores_menus_without_session_rows and the_harness_picker_is_no_wider_than_its_rows_and_keeps_its_keys_in_the_footer fail on main too; this PR doesn't touch them.

🤖 Generated with Claude Code

[davidbudac]

Hi Cody, this is just a tiny little change I was missing, since it can be quite hard for me sometimes to see which card I'm in currently.