feat(client): purchased UAL tiers wired — lib/Clip addressing, stance enter/exits, turn-in-place (T-1088)

ual1.glb (120 clips) + ual2.glb (134) replace the free-tier subsets;
CharacterVisual loads both under explicit library names with lib/Clip exact
addressing (bare names keep cross-library search). Gait table re-pointed;
two new one-shot overlays in the gait machine: stance transitions
(Sprint/Crouch Enter/Exit, destination-Enter priority, clip-length timer,
movement never stalls) and turn-in-place (Turn90/180 L/R from shortest-arc
sign, >=60/135 deg idle yaw jumps, retrigger-guarded). All clip names
verified by dumping the imported GLBs. 70 gait tests + live smoke green
(both libraries load with exact counts).

S9 live-tune list: turn handedness (unverified headless — one-line swap),
TURN_SPEED_SCALE=2.0 compromise vs the snappy yaw ease, turn-on-stop feel.

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

client/scripts/sandbox/sandbox_constants.gd

@@ -56,20 +56,23 @@ const TURN_BUDGET_DEG := {
 
 # -- Animation (design §6) -------------------------------------------------------
 
-## Gait table (§6.1) — the ONLY place animation clip strings live.
-## Clip names are the imported bare names: library "", "_Loop" stripped by the glTF
-## importer, case-sensitive (design-input §2.2). Careful = Walk_Formal (D-053 stance
-## readability at ortho distance; fallback if it reads "parade march": Walk at 0.6x —
-## one table cell). Jog_Fwd is the reserve if Sprint reads too aggressive at 2.5 m/s.
+## Gait table (§6.1) — the ONLY place gait clip strings live. Explicit "lib/Clip"
+## addressing (D-248 / T-1088): every locomotion loop lives in the UAL1 tier. Names
+## are the verified imported names (dumped 2026-07-06 from ual1.glb): the glTF importer
+## strips the "_Loop" suffix and sets loop mode, so "Walk_Loop" -> "Walk" (loop=1).
+## Careful = Walk_Formal (D-053 stance readability at ortho distance; fallback if it
+## reads "parade march": Walk at 0.6x — one table cell). Jog_Fwd (ual1) is the reserve
+## if Sprint reads too aggressive at 2.5 m/s.
 const GAIT_CLIP := {
-	"Sprint": {"idle": &"Idle", "moving": &"Sprint"},
-	"Walk": {"idle": &"Idle", "moving": &"Walk"},
-	"Careful": {"idle": &"Idle", "moving": &"Walk_Formal"},
-	"Crouch": {"idle": &"Crouch_Idle", "moving": &"Crouch_Fwd"},
+	"Sprint": {"idle": &"ual1/Idle", "moving": &"ual1/Sprint"},
+	"Walk": {"idle": &"ual1/Idle", "moving": &"ual1/Walk"},
+	"Careful": {"idle": &"ual1/Idle", "moving": &"ual1/Walk_Formal"},
+	"Crouch": {"idle": &"ual1/Crouch_Idle", "moving": &"ual1/Crouch_Fwd"},
 }
 
 ## Native clip ground speed (m/s) for cadence sync (§6.2):
 ## speed_scale = clamp(rig_speed / NATIVE_MPS[clip], SPEED_SCALE_CLAMP.x, .y).
+## Keyed by clip BASENAME (the part after "lib/") so it is addressing-agnostic.
 ## Initial guesses — tuned live against the DebugHud readout.
 const NATIVE_MPS := {"Walk": 1.4, "Walk_Formal": 1.2, "Sprint": 3.2, "Crouch_Fwd": 0.9}
 const SPEED_SCALE_CLAMP := Vector2(0.6, 1.8)
@@ -84,6 +87,58 @@ const BLEND := {
 	"teleport": 0.0,
 }
 
+# -- Stance-transition one-shots (T-1088; UAL1 Enter/Exit clips) ----------------------
+#
+# On a stance change, if the destination stance has an Enter clip OR the source stance
+# has an Exit clip, play that one-shot (loop=0) and blend into the target loop when it
+# elapses. The rig position channel is independent, so the character keeps gliding while
+# the transition plays (movement never stalls). Only Sprint and Crouch have Enter/Exit
+# clips in UAL1 (verified 2026-07-06); Walk/Careful transition with a plain gait blend.
+# Priority when both apply (only Crouch<->Sprint): destination Enter wins over source
+# Exit — "entering the new stance" is the salient action. Live-tune the edge if it reads
+# wrong. Names are verified imported names (all loop=0 one-shots).
+const STANCE_ENTER_CLIP := {
+	"Sprint": &"ual1/Sprint_Enter",
+	"Crouch": &"ual1/Crouch_Enter",
+}
+const STANCE_EXIT_CLIP := {
+	"Sprint": &"ual1/Sprint_Exit",
+	"Crouch": &"ual1/Crouch_Exit",
+}
+## Cross-fade (s) INTO a stance-transition one-shot. The blend back OUT to the target
+## loop reuses the BLEND table (crouch clips take BLEND.crouch).
+const STANCE_TRANSITION_BLEND := 0.12
+
+# -- Turn-in-place one-shots (T-1088; UAL1 Turn90, UAL2 Turn180) ----------------------
+#
+# When IDLE and the yaw TARGET jumps (mouse-driven octant snap) by >= TURN_TRIGGER_DEG,
+# play a turn one-shot synced to the rig's yaw ease, then fall back to the stance idle
+# clip. L/R is chosen from the sign of the shortest-arc delta; >= TURN_180_DEG uses the
+# 180 clip (UAL2). Retrigger is guarded — a fresh turn cannot start until the current
+# one elapses. Octants snap at 45 deg, so effective triggers are 90 deg -> Turn90 and
+# 135/180 deg -> Turn180. Names are verified imported names (all loop=0 one-shots).
+## Minimum yaw-target jump (deg) that triggers a turn-in-place. Below this, the rig's
+## normal yaw ease handles the reface with no clip.
+const TURN_TRIGGER_DEG := 60.0
+## At/above this jump (deg), use the Turn180 clip instead of Turn90.
+const TURN_180_DEG := 135.0
+## Turn one-shot clips keyed by "<arc>_<hand>". Turn90 is UAL1, Turn180 is UAL2.
+## Hand: positive shortest-arc yaw delta -> "_L", negative -> "_R" (VERIFY handedness
+## live — a swap is a one-line fix if the model turns the wrong way).
+const TURN_CLIP := {
+	"90_L": &"ual1/Turn90_L",
+	"90_R": &"ual1/Turn90_R",
+	"180_L": &"ual2/Turn180_L",
+	"180_R": &"ual2/Turn180_R",
+}
+## Cross-fade (s) into and out of a turn one-shot.
+const TURN_BLEND := 0.15
+## Playback rate for turn one-shots. The UAL turn clips are deliberate (~1.7-2.0 s); the
+## rig's idle yaw ease is snappy (~0.3 s for 180 deg), so at 1.0x the turn shuffle drags
+## long past the settled body. 2.0x is an initial compromise — S9 live-tunes it against
+## the on-screen yaw-ease duration (raise to shorten the turn, lower for weightier turns).
+const TURN_SPEED_SCALE := 2.0
+
 # -- Camera (design §7; D-148, D-015, D-158) -------------------------------------
 
 ## Pitch presets in degrees from horizontal — D-148 preset list is authoritative;