feat(stage): complete phase 20b action plans

docs/specs/phase_17a_prop_roles.md

@@ -137,9 +137,9 @@ Add `set_down_prop` to `ActionRegistry`, `ActionEditor`, stickman action popup,
 
 The interactor adds SET_DOWN_APPROACHING and SET_DOWN_REACHING (or equivalent explicit substates), with one shared nonmutating solver for authoring preview and PLAY validation. It reuses the queued held-prop preview prefix from Throw to determine the prop, grip, hand, and predicted actor pose. The prefix evaluator must also consume earlier Set Down actions as release actions and account for Drop/Throw; it may return `known=false` when a rule or earlier action makes the held prop uncertain. Do not move or reserve a live prop during preview. When unknown, show the neutral marker and **Prop depends on earlier actions**, and assess grounded approach/reach where possible without pretending to know exact occupancy. As with the existing Throw preview, cache physics shape checks in `_physics_process()` and draw the latest result in `_process()`; do not perform fresh direct-space queries from every pointer draw.
 
-For a known prop, retain its current held orientation and authored/play scale. Treat `target_position` as the requested release origin, then check the prospective collision shape against terrain and released-profile actor/prop contacts; exclude the held prop's own RID but check the acting rig's torso/head and other solid parts when released actor bumps are On. If the shape overlaps terrain or a prop whose **Holds other props** setting is On, raise the prospective origin vertically just enough to clear the overlapping support geometry. Do not shift it sideways or select a named surface. Keep the requested point unchanged in the saved action. If the shape overlaps the acting character or a non-support prop, reject it with **No room to let go here**. Do not add an implicit owner-collision grace period or permit release inside the torso. An open-air point remains exactly where clicked. Compute the grip position from the resolved transform and asset anchor, then solve a grounded approach on terrain to either side and check wrist/IK reach. Do not teleport the actor or clamp the point to make it reachable. Preview the requested point and corrected release origin when they differ. Re-resolve at runtime because actors and props may have moved since authoring. If the route is blocked or the point remains occupied, keep the prop held, restore its hand pose, show **Too far to reach** or **No room to let go here**, finish the action safely, and let the child edit the target. If no prop is held, show a short cue on that actor and finish safely without creating or dropping a prop.
+For a known prop, retain its current held orientation and authored/play scale. Treat `target_position` as the requested release origin, then check the prospective collision shape against terrain and released-profile actor/prop contacts; exclude the held prop's own RID but check the acting rig's torso/head and other solid parts when released actor bumps are On. If the shape overlaps terrain or a prop whose **Holds other props** setting is On, raise the prospective origin vertically just enough to clear the overlapping support geometry. Do not shift it sideways or select a named surface. Keep the requested point unchanged in the saved action. If the shape overlaps the acting character or a non-support prop, reject it with **No room to let go here**. An open-air point remains exactly where clicked. Compute the grip position from the resolved transform and asset anchor, then solve a grounded approach on terrain to either side and check wrist/IK reach. Do not teleport the actor or clamp the point to make it reachable. Preview the requested point and corrected release origin when they differ. Re-resolve at runtime because actors and props may have moved since authoring. If the route is blocked or the point remains occupied, keep the prop held, restore its hand pose, show **Too far to reach** or **No room to let go here**, finish the action safely, and let the child edit the target. If no prop is held, show a short cue on that actor and finish safely without creating or dropping a prop.
 
-During the reach, move the held prop smoothly with the hand marker toward the resolved release transform. If the point is low, bend the torso and knees during the reach, then release the prop and ease the arm and body back to their resting pose. At release, use the resolved origin and apply `RELEASED` with zero launch velocity so gravity carries the prop onto the surface. The support prop's collision geometry and gravity determine where the object settles. While held, the prop has no collision layer or mask; released collision settings take effect at the release moment. A pause freezes the animation and prop state. Ordinary action cancellation before release keeps the prop held and restores the marker; ragdoll aborts Set Down and uses the existing forced-release path with the authored released profile. STOP restores authored placement. Preserve the existing grip attachment logic and scale conversion rather than assuming an unscaled local anchor.
+During the reach, move the held prop smoothly with the hand marker toward the resolved release transform. If the point is low, bend the torso and knees during the reach, then release the prop and ease the arm and body back to their resting pose. At release, use the resolved origin and apply `RELEASED` with zero launch velocity so gravity carries the prop onto the surface. The support prop's collision geometry and gravity determine where the object settles. While held, the prop has no collision layer or mask; released collision settings take effect at the release moment. For a pickup, when the actor reserves its target, add an owner-specific contact exception between that target and the reserving rig's animated and ragdoll collision bodies. Keep it while `interaction_reserved_by` names that rig, regardless of distance or elapsed time; the owner's movement sweeps also skip only that target. On successful pickup, the `HELD` role clears the exception with the collision profile. On cancel or failure, release the reservation but retain an exit grace until the actor's collision shapes clear the prop by a 24 px query margin for two consecutive physics frames. For Set Down, add the same owner-specific exception after release and keep it until those shapes clear by that margin. Neither behavior changes authored collision flags or contact with the support, other props, or other stickmen; normal contacts resume after clearance. These protections are owner-specific and clearance-based, not inherited from the support; pickup protection lasts for the full reservation so it cannot expire while the actor is far away. Drop, Throw, and ragdoll forced release keep their authored contact behavior. A pause freezes the animation and prop state. Ordinary action cancellation before release keeps the prop held and restores the marker; STOP clears temporary exceptions and restores authored placement. Preserve the existing grip attachment logic and scale conversion rather than assuming an unscaled local anchor.
 
 ## Stage UI, selection, and theme
 
@@ -151,6 +151,6 @@ Use `SandboxTheme.control_theme()` on the card and popup. Read dimensions, fonts
 
 ## Regression checklist
 
-For future regression runs, use `tests/test_phase17a_prop_roles.gd` for role defaults/migration, queue and rule Set Down serialization, unknown-prop preview, released-vs-held transitions, and support contact, followed by Godot headless syntax validation. A small runtime scene can check that a support-only table catches a released pot while a stickman passes through, that switching **Can bump into other props** Off makes the pot fall through the table but still land on terrain, and that **Blocks stickmen** stops walking instead of letting the root tunnel through. Reopen saved scenes, copy a placement, select a fully occluded prop, and check correction of a bad Set Down target. Repeat PLAY after STOP and confirm identical authored arrangement, role settings, and usable stable IDs. Check pause/resume during holding and after release, plus ragdoll release.
+For future regression runs, use `tests/test_phase17a_prop_roles.gd` for role defaults/migration, queue and rule Set Down serialization, unknown-prop preview, released-vs-held transitions, support contact, Set Down owner-collision grace, and reserved-pickup protection, followed by Godot headless syntax validation. A runtime Set Down followed immediately by Move should confirm that the releasing stickman can clear the prop without knocking it away, the temporary exception is removed after clearance, a different stickman can still contact it, and the prop still rests on its support. A reserved pickup should stay protected through a long approach, clear on successful pickup, and transition to exit grace on cancellation/failure. Also verify that switching **Can bump into other props** Off makes the pot fall through the table but still land on terrain, and that **Blocks stickmen** stops walking instead of letting the root tunnel through. Reopen saved scenes, copy a placement, select a fully occluded prop, and check correction of a bad Set Down target. Repeat PLAY after STOP and confirm identical authored arrangement, role settings, and usable stable IDs. Check pause/resume during holding and after release, plus ragdoll release.
 
 The approved table/pot, open-air Set Down, invalid-target feedback, overlap chooser, card readability, old-scene replay, and movement-blocking behavior are useful visual/runtime regression scenarios.