feat(simulation): auto-pause sim on implant-fullscreen — inspection substrate (T-970)

D-226 layer 1. World-advancing phases gated on pause: Movement/Storyteller/Knowledge/TickAdvance set-gated via sim_not_paused; Simulation + Economy gated per-system at their registration sites — collect_sound_events and serve_econ_state_query stay unconditioned (transient-buffer clear + paused-allowed query; set-gating Simulation leaked a stale tick-7 footstep into frozen snapshots — caught by golden_suite, fixed without touching the fixture; regression test encodes the bug shape). New PlayerAction::AutoPause/AutoResume + AutoPauseState resource implement Option A reconciliation: auto-resume only fires if auto-pause caused the pause; manual pause and Half rate survive implant open/close. PauseParams SystemParam bundle keeps process_player_input under the 16-param ceiling (BookmarkInputParams precedent). Client: HudGroups.gameplay_occluded now sends AutoPause/AutoResume via send_named_action; 5 gdUnit tests + 7 Rust tests.

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

client/scripts/autoloads/hud_groups.gd

@@ -45,6 +45,28 @@ var _active_app: String = ""  # currently focused implant app ("" = none)
 var _active_mode: Mode = Mode.GAMEPLAY
 
 
+func _ready() -> void:
+	# T-970 (D-226 layer 1): auto-pause/auto-resume the sim when a fullscreen
+	# implant app occludes gameplay. AutoPause/AutoResume are distinct
+	# PlayerAction variants from the manual Pause/Unpause (Space bar, D-088) —
+	# the server tracks whether ITS OWN auto-pause caused the current pause
+	# (AutoPauseState) so a pre-existing manual pause or Half rate survives
+	# implant open/close untouched (see server/src/simulation/input.rs and
+	# server/src/simulation/time.rs).
+	gameplay_occluded.connect(_on_gameplay_occluded_auto_pause)
+
+
+## Sends AutoPause/AutoResume via SimBridge's outbound queue. Uses
+## send_named_action (protocol-level, not bound to an InputMapper.Action
+## keybind) — the same mechanism as RequestBookmarkCatalog — since occlusion
+## is a UI-state transition, not a physical input.
+func _on_gameplay_occluded_auto_pause(occluded: bool) -> void:
+	if occluded:
+		SimBridge.send_named_action("AutoPause")
+	else:
+		SimBridge.send_named_action("AutoResume")
+
+
 func register(node: CanvasItem, group: String) -> void:
 	if not _groups.has(group):
 		_groups[group] = []

client/tests/test_hud_groups_auto_pause.gd

@@ -0,0 +1,84 @@
+class_name TestHudGroupsAutoPause
+extends GdUnitTestSuite
+## T-970 (D-226 layer 1): HudGroups.gameplay_occluded must auto-pause/auto-resume
+## the sim via SimBridge.send_named_action("AutoPause"/"AutoResume").
+##
+## AutoPause/AutoResume are protocol-level requests, not InputMapper keybinds —
+## same mechanism as RequestBookmarkCatalog (send_named_action bypasses
+## action_enum_to_wire entirely, so there is nothing to map there). This suite
+## only covers the signal -> outbound-action wiring in hud_groups.gd; the
+## server-side pause reconciliation (Option A) is covered by Rust tests in
+## server/src/simulation/input.rs.
+
+const TEST_APP_PATH := "implant/test_auto_pause"
+const OTHER_APP_PATH := "implant/test_auto_pause_other"
+
+
+func before_test() -> void:
+	SimBridge.connect_to_sim()  # test mode: immediately CONNECTED
+	SimBridge._outbound_buffer.clear()
+	HudGroups._active_app = ""
+	HudGroups._active_mode = HudGroups.Mode.GAMEPLAY
+
+
+func after_test() -> void:
+	HudGroups._active_app = ""
+	HudGroups._active_mode = HudGroups.Mode.GAMEPLAY
+	HudGroups._groups.erase(TEST_APP_PATH)
+	HudGroups._groups.erase(OTHER_APP_PATH)
+	SimBridge.disconnect_from_sim()
+	SimBridge._outbound_buffer.clear()
+
+
+func _outbound_has_action(action_name: String) -> bool:
+	for entry in SimBridge._outbound_buffer:
+		if entry.get("action_name") == action_name:
+			return true
+	return false
+
+
+func test_opening_fullscreen_app_sends_auto_pause() -> void:
+	HudGroups.open_app(TEST_APP_PATH, HudGroups.Mode.FULLSCREEN)
+	assert_bool(_outbound_has_action("AutoPause")).override_failure_message(
+		"Entering a fullscreen implant app must send AutoPause"
+	).is_true()
+
+
+func test_closing_fullscreen_app_sends_auto_resume() -> void:
+	HudGroups.open_app(TEST_APP_PATH, HudGroups.Mode.FULLSCREEN)
+	SimBridge._outbound_buffer.clear()
+	HudGroups.close_app()
+	assert_bool(_outbound_has_action("AutoResume")).override_failure_message(
+		"Closing a fullscreen implant app must send AutoResume"
+	).is_true()
+
+
+func test_insert_mode_does_not_send_auto_pause() -> void:
+	# INSERT mode does not occlude gameplay (D-170) — gameplay_occluded never
+	# fires, so no AutoPause should be sent.
+	HudGroups.open_app(TEST_APP_PATH, HudGroups.Mode.INSERT)
+	assert_bool(_outbound_has_action("AutoPause")).override_failure_message(
+		"INSERT mode must not trigger AutoPause — gameplay is not occluded"
+	).is_false()
+
+
+func test_switching_between_fullscreen_apps_does_not_resend_auto_pause() -> void:
+	# D-170: switching from one fullscreen app to another must not re-emit
+	# gameplay_occluded (occlusion state does not change) — no duplicate AutoPause.
+	HudGroups.open_app(TEST_APP_PATH, HudGroups.Mode.FULLSCREEN)
+	SimBridge._outbound_buffer.clear()
+	HudGroups.open_app(OTHER_APP_PATH, HudGroups.Mode.FULLSCREEN)
+	assert_bool(_outbound_has_action("AutoPause")).override_failure_message(
+		"Switching between two fullscreen apps must not re-send AutoPause"
+	).is_false()
+
+
+func test_toggle_app_closed_from_fullscreen_sends_auto_resume() -> void:
+	# toggle_app(app) when already open calls close_app() internally —
+	# exercises the same gameplay_occluded(false) path via a different entry point.
+	HudGroups.open_app(TEST_APP_PATH, HudGroups.Mode.FULLSCREEN)
+	SimBridge._outbound_buffer.clear()
+	HudGroups.toggle_app(TEST_APP_PATH)
+	assert_bool(_outbound_has_action("AutoResume")).override_failure_message(
+		"toggle_app() closing a fullscreen app must send AutoResume"
+	).is_true()