fix(ui): render armed record 148 item region

Record 148 publishes player item 20 and refreshes word-quad 20 through overlay
A. Its recovered bounds are (9,14)-(25,30). Rust tracked the armed special hole
but never rendered this visible 17x17 table state.

Expose the armed/active special-hole state and composite the exact DAT997 region
until the special respawn consumes record 148's contact. Make the deterministic
effect-seven scenario internally valid by seeding the required contact, so its
framebuffer now covers both the DAT407 effect and item 20.

Test Plan:
- `cargo test --workspace --all-targets --all-features` -- 120 passed
- `cargo clippy --workspace --all-targets --all-features -- -D warnings` -- passed
- `rumdl check --flavor commonmark RECONSTRUCTION.md CHANGELOG.md` -- passed
- `cargo run -- --simulate effect-7 --step 0 --screenshot /tmp/tdkpin-effect7-special.png` -- passed; visually inspected at 640x460
- launcher/effect screenshot comparison -- 136 RGB pixels differ inside only the expected 17x17 item region
- `git diff --cached --check` -- passed

tdkpin-rs/src/game.rs

@@ -446,6 +446,10 @@ impl Game {
     pub(crate) fn begin_effect_scenario(&mut self, effect: u8) {
         self.target_effect = effect.min(7);
         self.object_active[usize::from(EFFECT_SENSOR.id)] = self.target_effect != 0;
+        if self.target_effect == 7 {
+            self.multiball_state = MultiballState::Ready;
+            self.record_contacts[148] = 2;
+        }
     }
 
     fn fire_launcher(&mut self) {
@@ -1937,6 +1941,13 @@ impl Game {
         self.object_active[usize::from(EFFECT_SENSOR.id)]
     }
 
+    pub fn special_hole_active(&self) -> bool {
+        matches!(
+            self.multiball_state,
+            MultiballState::Ready | MultiballState::Active
+        )
+    }
+
     pub fn player_effect(&self) -> u8 {
         self.target_effect.min(7)
     }
@@ -2794,6 +2805,7 @@ mod tests {
             .secondary_ball
             .expect("effect seven should spawn a second ball");
         assert_eq!(game.multiball_state, MultiballState::Active);
+        assert!(game.special_hole_active());
         assert_eq!(spawned.position, vec2(17.0, 23.0));
         assert_eq!(
             MilliVec::from_velocity_per_second(spawned.velocity),
@@ -2822,6 +2834,7 @@ mod tests {
             MilliVec { x: 0, y: 3_040 }
         );
         assert_eq!(game.multiball_state, MultiballState::Unavailable);
+        assert!(!game.special_hole_active());
         assert_eq!(game.record_contacts[148], 0);
         assert_eq!(game.special_hole_gate, SpecialHoleGate::Suppressed);