Restore ADV wait indicator

docs/engine-re.md

@@ -1050,6 +1050,29 @@ Matching evidence: `build/native-adv-text-trace.jsonl` and Godot timeline captur
 non-overlapping name/dialogue bands at y=447–468, 478–500, and 507–530. A manual run progressed 14 pages:
 11 clicks completed active reveals and 14 later clicks released 14 distinct waits through `0xe0c`.
 
+#### ADV wait indicator -- ops `0x73` / `0x72` (2026-07-11)
+
+The small bat marker is a configured ADV-layout sprite, not a glyph or part of SO001. `SYSTEM4.BIN`
+loads universal raw asset `0x337c` (`SO000.AGF`) into surface slot 12. SO000 is a 390x27 strip of thirteen
+30x27 bat frames. It then executes op `0x73` with
+`(layout=1, x=385, y=140, surface=12, src=0,0, cell=30x27, terminalFrame=12, period=48ms)`.
+Layout 1 begins at screen y=430, so the marker lands at `(385,570)`, matching the original screenshot.
+
+Native `op_0x73_configure_wait_indicator@0x41e900` writes this descriptor through
+`adv_text_configure_wait_indicator@0x44ff60` to layout fields `+0x3c..+0x60`; operand 10 configures the
+animation period through `adv_indicator_set_frame_period@0x44d060`. `op_0x72_handler@0x41e690` later calls
+the layout renderer with frame `-1` and arms the input-wait flags, which makes the configured animation
+visible only after show-text has naturally or forcibly completed. The completion click remains consumed;
+the following click releases the wait.
+
+**Port implementation:** the single-scene harness now injects SYSTEM4's exact SO000 surface-12 and op-`0x73`
+configuration alongside its existing SO001 shortcut. The VM forwards all ten operands through the host ABI;
+`GodotAdvHost` retains configurations by layout and resolves slot 0 to the active Phase-A layout. A separate
+Godot atlas overlay advances the inclusive frames `0..12` on the 48 ms host clock only while `IsWaiting`,
+then hides immediately when input releases the wait. Keeping this 30x27 overlay outside the software
+backbuffer preserves the static-wait compositor optimization. Full SYSTEM4 replay remains Phase-B work;
+the shortcut carries the same state in the meantime.
+
 ### SC0000 native SFX / BGM-fade family — `0xb4`/`0xb5`/`0xb6`/`0xc2`/`0xd9` (2026-07-11)
 
 The three SFX opcodes are a retained channel lifecycle, not immediate fire-and-forget calls. Handler

docs/opcode-reference.md

@@ -5,6 +5,16 @@
 
 ## adv
 
+### 0x72 `wait-for-input` (wait-for-input, argc 1)
+- **summary:** (layout_slot) - arm the ADV input wait after text reveal completes; activates the wait indicator configured for the selected text layout by op 0x73.
+- **grounding:** source=investigation, confidence=high
+- **evidence:** Ghidra /v2: op_0x72_handler@0x41e690 fetches operand 1 and calls FUN_00453120(text_manager, layout_slot, -1, &state), then sets the input-wait run-state flags. FUN_00453120 resolves layout slot 0 as current and consumes the indicator descriptor at layout+0x3c configured by op 0x73. SYSTEM4 layout 1 uses SO000's bat strip; the click that completes show-text is consumed before this opcode is reached.
+
+### 0x73 `configure-adv-wait-indicator` (configure-adv-wait-indicator, argc 10)
+- **summary:** (layout_slot)(dst_x)(dst_y)(surface_slot)(src_x)(src_y)(cell_w)(cell_h)(terminal_frame)(frame_period_ms) - configure the animated marker shown while the selected ADV layout waits for input.
+- **grounding:** source=investigation, confidence=high
+- **evidence:** Ghidra /v2: op_0x73_configure_wait_indicator@0x41e900 passes operands 1..9 to adv_text_configure_wait_indicator@0x44ff60 and operand 10 to adv_indicator_set_frame_period@0x44d060. The worker writes surface/source rect, layout-relative destination, enabled=1, and terminal/column values to the selected layout at +0x3c..+0x60. SYSTEM4 executes `set-texture 0x337c 0xc 0xff00` (raw id 0x337c = SO000.AGF, a 390x27 strip of thirteen 30x27 bat frames), then `0x73 1 385 140 12 0 0 30 27 12 48`; layout 1 begins at y=430, placing the 30x27 marker at screen (385,570), matching the original. Op 0x72 activates this descriptor only after reveal completion.
+
 ### 0x7a `set-adv-text-cursor` (set-adv-text-cursor, argc 3)
 - **summary:** (layout_slot)(x)(y) - set the cursor in the selected ADV text layout's last 20-byte record. Slot 0 selects the current layout.
 - **grounding:** source=investigation, confidence=high
@@ -524,14 +534,6 @@ op 0x90 (u0041BEB0, argc 7): `0x90 x y w h tgt_a tgt_b tgt_c`. Kelebek left it "
 - **summary:** —
 - **grounding:** source=kelebek, confidence=low
 
-### 0x72 `wait-for-input` (wait-for-input, argc 1)
-- **summary:** —
-- **grounding:** source=kelebek, confidence=med
-
-### 0x73 `u0041AB30` (u0041AB30, argc 10)
-- **summary:** —
-- **grounding:** source=kelebek, confidence=low
-
 ### 0x75 `u0041AC30` (u0041AC30, argc 1)
 - **summary:** —
 - **grounding:** source=kelebek, confidence=low

docs/phase-a-slice-plan.md

@@ -1384,6 +1384,18 @@ visible. This AE001D path is a retained scaled/rotating texture; the later `0x23
 was separately resolved by preserving draw-texture's 200x200 cell and interpreting `(8,4)` as total
 frames/columns rather than a grid divisor.
 
+### SC0000 ADV wait indicator implemented (2026-07-11)
+
+The missing post-reveal bat is `SO000.AGF`, a 390x27 strip of thirteen 30x27 frames. SYSTEM4 loads raw
+asset `0x337c` into surface slot 12 and configures layout 1 through op `0x73` as a marker at layout-relative
+`(385,140)`, screen `(385,570)`, with terminal frame 12 and a 48 ms period. Native op `0x72` activates that
+layout descriptor after reveal completion. The Phase-A bootstrap now injects SO000 into surface 12 and
+forwards the exact op-`0x73` configuration through `IHost`; `WaitForInput` carries the selected layout and
+starts the marker clock. Godot presents it as a separate 30x27 atlas overlay, advancing inclusive frames
+0..12 every 48 ms only during the stable wait and hiding on release. This avoids recompositing the 800x600
+software backbuffer during otherwise static waits. Validation: engine **147/147**, zero-warning Godot build,
+threaded `SELFTEST OK`, and a real page-1 capture showing the transparent bat at `(385,570)`.
+
 ### A2b -- SC0000 post-movie AE001H spritesheet correction ✅ DONE (2026-07-11)
 
 The reported missing cave spirit was the `0x231` path, independent of the earlier AE001D retained glow.