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>

Cargo.lock

@@ -2777,6 +2777,7 @@ version = "0.8.2"
 dependencies = [
  "anyhow",
  "ash",
+ "pf-client-core",
  "pf-presenter",
  "sdl3",
  "skia-safe",
@@ -3012,6 +3013,7 @@ dependencies = [
  "pf-console-ui",
  "pf-presenter",
  "punktfunk-core",
+ "serde_json",
  "tracing",
  "tracing-subscriber",
 ]