feat(session): console game library — Skia coverflow + SkSL aurora, --browse (phase 4b)

The run loop grows a browse mode: the console library idles between
streams in ONE window (no gamescope handoff), overlay actions launch
sessions via run_browse's callback, session end returns to the library.
The Overlay contract gains menu routing (MenuEvent → haptic pulse),
action draining, and session-phase edges.

pf-console-ui ports the GTK launcher wholesale: the coverflow's springs,
cursor arithmetic and recede/tilt constants move verbatim with their
tests (plus new projection tests — focused-card centering, the inner-
edge-recedes corridor); paint order is draw order (the gtk::Fixed
restack hack is gone); the aurora renders as an SkSL runtime shader at
full rate on every box (the 30 Hz CPU-upscale path and its frozen-on-
Deck fallback are deleted — the generated SkSL is compile-tested);
titles/scenes shape through textlayout (CJK-safe). Poster art streams
in as encoded bytes through the shared model and decodes renderer-side.

The session binary wires --browse host[:port] [--mgmt PORT]: KnownHosts
lookup (unpaired renders the pair-first scene), library + art fetch on
threads, PUNKTFUNK_FAKE_LIBRARY dev hook, and a session_params helper
shared with --connect. The minimal build refuses --browse cleanly.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

crates/pf-console-ui/src/lib.rs

@@ -8,8 +8,14 @@
 //! purpose, it proves the whole shared-device pipeline. The gamepad library moves in
 //! next.
 
+#[cfg(target_os = "linux")]
+pub mod library;
+#[cfg(target_os = "linux")]
+mod library_ui;
 #[cfg(target_os = "linux")]
 mod skia_overlay;
 
+#[cfg(target_os = "linux")]
+pub use library::{LibraryGame, LibraryPhase, LibraryShared};
 #[cfg(target_os = "linux")]
 pub use skia_overlay::SkiaOverlay;