The KWin backend names its output Virtual-punktfunk-<id> from the client's
stable identity slot, so KWin persists per-output config (scale/mode) by name in
kwinoutputconfig.json and reapplies that client's scaling on reconnect — the KDE
scaling ask. Also fixes the latent clash where two concurrent sessions both used
Virtual-punktfunk (topology name-matching now uses the per-slot name).
- identity::global() + resolve_slot(fp, mode, default) — the shared persisted map
(Windows manager dropped its own field; both use the global — never same-process).
Default identity is per-platform: PerClient on Windows, Shared on Linux, so
unconfigured hosts keep today's behavior (Linux = single 'punktfunk' name).
- KwinDisplay carries the client fp (set_client_identity), computes the per-slot
name, threads it through the stream_virtual_output name + the topology helpers
(set_custom_refresh / apply_virtual_primary[_only] / other_enabled_outputs).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Generalize the Windows-only per-client stable-id map into vdisplay/identity.rs:
- DisplayIdentityMap keyed on a composable string (identity_key: fingerprint,
or fingerprint+resolution under per-client-mode); LRU at 15, persisted to
display-identity.json (migrated from the legacy pf-vdisplay-identity.json).
- Windows manager wired to it, picking the key from the identity policy.
- Foundation for KWin per-slot output naming (persistent KDE scaling) — the
KWin wiring is the next Stage-3 step (needs a KWin box).
- Unit-tested (stable, per-client-mode split, LRU, key composition).
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
enricobuehler