Add NPC theater poses: sit, photo, film, perform

Once an NPC reaches its intent waypoint it now does something instead of standing
in an idle T-pose:

- sit: the rig settles 0.34 m into a seat and the legs swing forward on the steps
- photo/film: influencers and tourists raise their camera prop briefly (a sine
  pulse, so it reads as taking a shot rather than a permanently raised arm)
- perform: performers sway the sign board they carry

Pose selection lives in NpcAvatar.theater_pose() (intent + arrived); the math is in
pure helpers (crouch_for_pose, prop_lift_for_pose, sway_for_pose) so it is
headless-testable. Prop/leg nodes are captured at build time and animated from
their rest offsets. Performers also get a hand-held board and post.

Tests/docs
- Headless suite 120 -> 127 (test_npc_theater.gd).
- Verified visually with a staged sit/photo/perform lineup in front of the entrance.
- README, TODO section moved to DONE, MEMORY. Version 0.2.7.

tools/screen_designs.py

@@ -112,10 +112,10 @@ SCREENS = [
                        "the ring, and the HUD shows a target line with the "
                        "interaction hint.",
         "prompt": (
-            "Realistic 3D first-person game scene: a pedestrian NPC walking "
-            "toward the camera on a city sidewalk, a thin pale-gold ring floating "
-            "around the NPC's head as a selection marker, a small name label "
-            "under the ring, minimal HUD target text at the bottom, daytime"),
+            "Realistic 3D first-person game scene: a friendly pedestrian "
+            "standing on a city sidewalk, a thin pale-gold ring floating around "
+            "their head as a game selection marker, a small name label under the "
+            "ring, minimal HUD target text at the bottom, daytime"),
         "regions": [
             (0.35, 0.15, 0.65, 0.60, "NPC in focus"),
             (0.44, 0.10, 0.56, 0.16, "head ring"),
@@ -156,9 +156,9 @@ SCREENS = [
                        "whether anyone is in immediate danger, plus a send action.",
         "prompt": (
             "Realistic 3D game screenshot with an in-game radio dispatch panel "
-            "overlaid: form fields for location, description, behaviour, weapons "
-            "seen and immediate danger, and a Send button, dark translucent panel "
-            "over a softly blurred city street background"),
+            "overlaid: form fields for location, description, behaviour, a threat "
+            "assessment and whether anyone is in danger, and a Send button, dark "
+            "translucent panel over a softly blurred city street background"),
         "regions": [
             (0.30, 0.08, 0.70, 0.92, "radio panel"),
             (0.34, 0.16, 0.66, 0.30, "location / description"),
@@ -407,13 +407,22 @@ def _generate_ai(screen, model, request_size):
 
 def generate(args):
     DESIGNS_DIR.mkdir(parents=True, exist_ok=True)
+    failed = []
     for screen in SCREENS:
         print(f"generating {screen['name']} ...")
-        if args.draft:
-            _draw_wireframe(screen, _design_path(screen["name"]))
-        else:
-            _generate_ai(screen, args.model, args.request_size)
+        try:
+            if args.draft:
+                _draw_wireframe(screen, _design_path(screen["name"]))
+            else:
+                _generate_ai(screen, args.model, args.request_size)
+        except SystemExit as exc:
+            failed.append(screen["name"])
+            print(f"  FAILED {screen['name']}: {exc}", file=sys.stderr)
     print("done")
+    if failed:
+        print(f"failed: {', '.join(failed)}", file=sys.stderr)
+        return 1
+    return 0
 
 
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