fix(client): address PR #13 review — LOS tests, reset consistency, docs

- Use reset_test_state() consistently in test_snapshot_parsing.gd (Tyre critical)
- Fix misleading wall comment: (12,9) → (12,10) (Hoshe warning)
- Add coordinate space documentation to _test_snapshot() (Tyre warning)
- Add 4 Bresenham LOS unit tests: clear, blocked, diagonal, self (Hoshe warning)
- Check OS.is_process_running() in connection loop (Hoshe warning)
- Verify NPC position in corner reveal test (Hoshe suggestion)

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

client/tests/test_snapshot_parsing.gd

@@ -51,11 +51,25 @@ func test_missing_fields_partial_update() -> void:
 	assert_that(GameState.player_position).is_equal(Vector2(10, 15))
 	assert_that(GameState.current_tick).is_equal(2)
 
+func test_sim_bridge_los_clear_path() -> void:
+	# No wall between (10,10) and (10,8) — clear LOS
+	assert_that(SimBridge._test_has_los(Vector2i(10, 10), Vector2i(10, 8))).is_true()
+
+func test_sim_bridge_los_blocked_by_wall() -> void:
+	# Wall at (12,10) blocks LOS from (10,10) to (12,9) via east path
+	# Direct line from (10,10) → (12,9) passes through (11,10) then (12,10) — wall
+	assert_that(SimBridge._test_has_los(Vector2i(10, 10), Vector2i(14, 10))).is_false()
+
+func test_sim_bridge_los_diagonal() -> void:
+	# Diagonal LOS from (10,10) to (11,9) — no wall in path
+	assert_that(SimBridge._test_has_los(Vector2i(10, 10), Vector2i(11, 9))).is_true()
+
+func test_sim_bridge_los_same_position() -> void:
+	# LOS to self is always true
+	assert_that(SimBridge._test_has_los(Vector2i(10, 10), Vector2i(10, 10))).is_true()
+
 func test_sim_bridge_test_snapshot_deterministic() -> void:
-	SimBridge._test_tick = 0
-	SimBridge._test_player_pos = Vector2i(10, 10)
-	SimBridge._test_facing = "North"
-	SimBridge._test_input_queue.clear()
+	SimBridge.reset_test_state()
 	var snap1 = SimBridge._test_snapshot()
 	var snap2 = SimBridge._test_snapshot()
 

client/tests/test_sprint2_proof.gd

@@ -91,6 +91,9 @@ func _connect_to_server() -> bool:
 	_bridge = LocalBridge.new()
 	var elapsed := 0.0
 	while elapsed < CONNECT_TIMEOUT:
+		if _server_pid > 0 and not OS.is_process_running(_server_pid):
+			push_warning("Server process died during connection")
+			return false
 		if _bridge.get_status() == StreamPeerTCP.STATUS_NONE:
 			_bridge.connect_to_server("127.0.0.1", _test_port)
 		_bridge.poll()
@@ -174,6 +177,8 @@ func test_proof_corner_reveal() -> void:
 	var npc_found := false
 	for entity in snapshot.entities:
 		if entity.kind.variant == "Npc":
+			assert_float(entity.x).is_equal_approx(16.5, 0.001)
+			assert_float(entity.y).is_equal_approx(13.5, 0.001)
 			npc_found = true
 			break
 	assert_that(npc_found).is_true()