design(task): hover-reveal the rename pencil like the other card controls

[johnpc]

Design-polish pass — continuing on the List view (per owner direction). With the empty date, "Unassigned", and "Low" defaults now all quieted (#191/#194/#195), the last bit of always-on chrome stood out: the rename pencil next to every task title, shown at rest in every list row (and every board card).

Root cause

The task-card hover-reveal treatment (DES#160) hides the quick-edit / reorder / multi-select controls at rest and reveals them on hover/focus — but the selector list never included .task-card__rename, so the pencil stayed visible in every row.

Fix (CSS-only, tokens only)

Added .task-card__rename to the existing @media (hover: hover) hide + reveal rules. A resting row/card now shows just its title; the pencil appears on row hover or keyboard focus, alongside the other quick-edit chrome. Touch devices (no hover) keep the pencil visible, so the rename affordance is never unreachable. Shared task.css, so this cleans up both the list rows and the board cards.

Before → after

• Rest — desktop (no pencils): https://files.jpc.io/d/haYiE-list-pencil-rest-desktop.png
• Hover — desktop (pencil + controls revealed on the hovered row): https://files.jpc.io/d/RYg2k-list-pencil-hover-desktop.png
• Mobile (pencil kept — touch has no hover): https://files.jpc.io/d/nYKGp-list-pencil-mobile.png

Full quality gate green; presentational-only. Verified against the sandbox (AWS_PROFILE=personal).