perf(capture): add SceneLens GPU streams and retained scene reuse

Use persistent privacy-filtered capture targets and client-owned GPU buffers with fence completion, backpressure, negotiated frame rates and shared-memory fallback.

Invalidate output views on scene changes while preserving inactive-window callbacks and capture revocation. Include OBS memory-mask negotiation and native pixel, transport and recording regressions.

Cargo.lock

@@ -1903,6 +1903,7 @@ dependencies = [
  "bitflags 2.13.2",
  "wayland-backend",
  "wayland-client",
+ "wayland-protocols",
  "wayland-protocols-wlr",
  "wayland-scanner",
  "wayland-server",
@@ -8259,6 +8260,7 @@ dependencies = [
  "ferese-theme",
  "ferese-theme-client",
  "futures-util",
+ "gbm",
  "gstreamer",
  "image",
  "jiff",