G1: Lift, soft elevation shadows (off by default)

`Lift` (a GUI toggle, capability lift) lifts the focused pane on a
critically damped spring (animation.Spring: closed form, about 240 ms to
settle, velocity kept across retargets, settled = no frames) and floats
notices. The core puts the lift on the regions (Region.lift, on the wire);
the GUI casts from it: a soft shadow is decor, an erf rectangle on one
quad grown by 3 sigma (decor.frag, flag 0x10000000), in the quad's own
space so a track's transform carries it; darken-only, the caster's rect
left alone, alpha pre-warped for linear light and IGN-dithered. Cast last
in its group, so a neighbour's rails and rules darken with its text; a
notice's before its rule. Strength is capped per theme so text over the
darkest shadow keeps min(its contrast, 4.5) (test over the native themes).

Opt-in until the focus lift/dim default is decided. Feel review material:
docs/effects.md. Test-mode PARDES_TEST_SERIES keeps every captured frame.

Shared files touched: pardes.zig (two fields, one nextWake line),
detached/wire.zig (lift on the region), config.zig, builtins.zig
(capability), gui.zig. Not touched: Messages.zig, mouse.zig, tty,
host_io.

1 files changed, 1 insertions, 1 deletions

diff --git a/shaders/ui.frag.glsl b/shaders/ui.frag.glsl
index 0b099db3..dca224ba 100644
--- a/shaders/ui.frag.glsl
+++ b/shaders/ui.frag.glsl
@@ -43,7 +43,7 @@ void main() {
     float bgA = (v_effect.x & 0x20000000u) != 0u ? 1.0
         : (v_effect.x & 0x40000000u) != 0u ? 0.0
         : clamp(u_ui.background_opacity, 0.0, 1.0);
-    uint effect = v_effect.x & 0x1fffffffu;
+    uint effect = v_effect.x & 0x0fffffffu;
     float progress = clamp(uintBitsToFloat(v_effect.y), 0.0, 1.0);
     uint cellCol = v_effect.w & 0xffffu;
     uint cellRow = v_effect.w >> 16;