Implement #160, #161, #162, #163, #164 and #165

#162 - a single tap bought a research node outright. One physical tap arrives
TWICE: Godot emulates a mouse button from every touch AND a touch from every
mouse button, both project settings are on, and the menu's dispatcher routes
InputEventScreenTouch and InputEventMouseButton alike to the tree. The second
arrival found the node already selected and took itself for the confirming
tap. Measured, not reasoned about - one tap produced two picks and two
confirms.

What is ignored is specifically the TWIN: same frame, same place, arriving
through the other input kind. Deduping on frame and position alone also
swallowed two genuine taps in one frame, which the test caught.

#164 - the build menu predicted a caption's height from the COLUMN WIDTH:
wide column, assume one line. Right for most names and wrong for the long
ones, so "Spacial Workshop" wrapped onto the price beneath it. Captions are
now measured against the font that draws them, and prices sized from
PriceTag.wanted_height(), which existed for exactly this and was not being
asked. Prices are set before anything is measured, because the old order laid
out first and priced afterwards.

The ship lab: its buy button is gone and a second tap on an option buys it,
the same rule as the research tree; the explanation drops into the room that
freed; research points move up into the resource table, where everything else
being spent already is; the second row of options is placed from the first
row's measured bottom rather than a constant; and the vessel strip is spaced
from the panel's own width, so the eighth vessel is no longer half off the
right edge.

#160 - the quest panel was drawn BEFORE the sticks and the pivot pair, so
they sat on top of it. Moved after them, under the narration banner. Its title
rule ran straight through the close button; the header band is now as tall as
that button.

#161 - the prologue widens the formation into a freight convoy by writing over
GameState.formation, and nothing put it back. The player flew the convoy's
600-unit spread for the rest of the game - a shape nobody chose, which reads
as the fleet having drifted apart.

#163 - a quest to station a vessel at the outpost, after the one that asks for
the outpost. Building one and crewing it are different acts, and an empty
outpost holds nothing.

#165 - the gas bomb's blast and a vessel arriving fast both damage a
structure. The blast used to stop politely at anything the player owned, which
made a bomb dropped on a besieged mothership a free way to sweep the attackers
off it.

Collisions are caught on ENTRY, not on the 0.7s strike tick: a vessel is only
moving fast for the instant it arrives, and a ship sent in at 900 did no
damage at all until this moved. Docking is free - the fleet sits on its own
mothership constantly to bank ore - and garrison vessels are exempt outright,
because they launch from their outpost and re-dock with it at speed. The suite
caught that one: the ram rule was destroying the garrison as it launched.

Suite 153/153. Four tests changed because what they pinned moved: the lab's
buy button, the intro's formation, the research tree's tap delivery, and the
build menu's own preview.

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

tests/test_building_collateral.gd

@@ -0,0 +1,134 @@
+extends SceneTree
+
+# Headless gameplay test: run with
+#   godot --headless -s res://tests/test_building_collateral.gd
+# Forgejo #165: a gas bomb and a vessel flying fast enough both damage a
+# structure. The blast used to stop politely at anything the player owned,
+# which made a bomb dropped on a besieged mothership a free way to sweep the
+# attackers off it.
+#
+# Covers:
+#   A. a bomb landing on a structure damages it
+#   B. a bomb landing clear of it does not - the radius is the radius, and
+#      this is a weapon that has to be aimed
+#   C. a vessel resting against a structure does NOT damage it. The fleet
+#      sits on its own mothership constantly to bank ore; if that hurt, the
+#      game's own economy loop would grind its buildings down
+#   D. a vessel arriving fast does
+
+var game_state: Node
+var main: Node
+var fleet: Node
+var building_id: int = 0
+var stage: int = 0
+var elapsed: float = 0.0
+var hp_before: int = 0
+const BUILDING_AT := Vector2(1200.0, 0.0)
+
+
+func _initialize() -> void:
+	game_state = root.get_node("GameState")
+	game_state.buildings.clear()
+	game_state.extractors.clear()
+	game_state.reset_progression()
+	main = load("res://world/Main.tscn").instantiate()
+	root.add_child(main)
+	current_scene = main
+	fleet = main.get_node("Fleet")
+
+
+func _hp() -> int:
+	return int(game_state.find_building(building_id).get("hp", 0))
+
+
+func _detonate_at(at: Vector2) -> void:
+	var bomb: Node2D = load("res://vfx/GasBombEffect.gd").new()
+	main.add_child(bomb)
+	bomb.target = at
+	bomb.damage = 6
+	bomb._explode()
+	bomb.queue_free()
+
+
+func _process(delta: float) -> bool:
+	elapsed += delta
+	match stage:
+		0:
+			if elapsed < 0.4:
+				return false
+			main.get_node("EnemySpawner").set_process(false)
+			main.get_node("AsteroidField").set_process(false)
+			for hazard in get_nodes_in_group("asteroids") + get_nodes_in_group("enemies"):
+				if is_instance_valid(hazard):
+					hazard.queue_free()
+			main.get_node("BuildingField").place(GameState.BUILDING_MOTHERSHIP, BUILDING_AT)
+			building_id = int(game_state.buildings[0].id)
+			if _hp() <= 0:
+				return _fail("the structure has no hit points to lose")
+			stage = 1
+			elapsed = 0.0
+			return false
+		1:
+			if elapsed < 0.2:
+				return false
+			# --- B. a bomb well clear of it does nothing ------------------
+			hp_before = _hp()
+			_detonate_at(BUILDING_AT + Vector2(900.0, 0.0))
+			if _hp() != hp_before:
+				return _fail("a bomb 900 away still damaged the structure")
+			print("a bomb clear of the structure leaves it alone")
+
+			# --- A. a bomb on top of it does --------------------------------
+			_detonate_at(BUILDING_AT)
+			if _hp() >= hp_before:
+				return _fail("a bomb landing on the structure did not damage it (hp %d)" % _hp())
+			print("a bomb on the structure took it from %d to %d" % [hp_before, _hp()])
+
+			# --- C. resting against it is free ------------------------------
+			hp_before = _hp()
+			fleet.spawn_ships(1, BUILDING_AT, PackedStringArray([GameState.VESSEL_INTERCEPTOR]))
+			for ship in fleet.ships:
+				ship.global_position = BUILDING_AT
+				ship.velocity = Vector2.ZERO
+			stage = 2
+			elapsed = 0.0
+			return false
+		2:
+			# Long enough for several strike ticks to have passed.
+			if elapsed < 2.0:
+				return false
+			for ship in fleet.ships:
+				ship.velocity = Vector2.ZERO
+			if _hp() != hp_before:
+				return _fail("a vessel resting on the structure damaged it (%d -> %d) - the fleet docks here to bank ore" \
+					% [hp_before, _hp()])
+			print("a vessel parked on the structure for %.1fs did nothing to it" % elapsed)
+
+			# --- D. arriving fast does --------------------------------------
+			hp_before = _hp()
+			for ship in fleet.ships:
+				# Placed clear and sent IN, because the impact is detected on
+				# entry - a ship spawned already overlapping never enters.
+				ship.global_position = BUILDING_AT - Vector2(400.0, 0.0)
+				ship.velocity = Vector2(900.0, 0.0)
+				ship.set_move_target(BUILDING_AT + Vector2(600.0, 0.0))
+			stage = 3
+			elapsed = 0.0
+			return false
+		3:
+			if elapsed < 1.2:
+				return false
+			if _hp() >= hp_before:
+				return _fail("a vessel arriving at 900 did not damage the structure")
+			print("a vessel arriving fast took it from %d to %d" % [hp_before, _hp()])
+
+			print("TEST_BUILDING_COLLATERAL: PASS")
+			quit(0)
+			return true
+	return false
+
+
+func _fail(message: String) -> bool:
+	print("TEST_BUILDING_COLLATERAL: FAIL (%s)" % message)
+	quit(1)
+	return true