Wires the sidebar's musician-clicked callback into a real
destination. Mirrors Tauri's MusicianPageView.svelte plus the
"jump to artist page when Confirmed" shortcut.
Slint:
- ContentView gains a `musician` variant; NavEntry mirrors with
`Musician { name, role }` so the back/forward history can
re-fire the page with the original payload.
- MusicianState / MusicianActions globals carry the resolved
musician metadata (name, role, confidence) + the paginated
Appears On grid (MusicianAppearanceItem mirrors the Tauri
interface — album_id, title, artist_name, year,
role_on_album, artwork URL/handle).
- New `ui/musician/MusicianPageView.slint`: header (avatar +
name + role), Bands & Projects chips when populated, and an
Appears On grid built from the same absolute-position pattern
the artist release grid uses. Load more button drives
MusicianActions::load-more.
- AppShell routes ContentView.musician to MusicianPageView and
forwards open-album.
Rust:
- `crate::musician` controller — load_musician, apply_musician,
load_more_appearances, append_appearances, reset_musician,
artwork_jobs. Pure data + UI plumbing; the orchestration lives
in qbz-core.
- artwork::ArtworkTarget gains MusicianAppearance { index } so
the existing artwork pipeline can target the new grid.
- main.rs gains `navigate_musician` (the navigation entry point
apply_entry now also routes to) and `on_musician_clicked`
(does the resolve, jumps to navigate_artist on Confirmed,
otherwise records + navigates to the Musician view).
- MusicianActions::on_load_more wired to load_more_appearances
+ append.
cc
