Three new heroes: giant, fairy spy, battle mage

- giant (from wave 6): slow and enormous, smashes doors three times as hard and wrecks traps by standing next to them
- fairy spy (from wave 3): flies, finds the dungeon's traps (marked with a glint) so the heroes wreck them, and heals heroes around it
- battle mage (from wave 4): throws fireballs with splash and blasts reinforced walls (steel resists him better)
- sprites, bestiary texts EN/DE, test: fairies find traps, giants wreck them

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

lang/en.lang

@@ -894,3 +894,12 @@ best.b.arena.text = Sand, sweat and the occasional tooth. Experience comes fast
 best.b.altar.text = Black marble that drinks. Some say it listens to pairs. Ogre and spider, mage and bat, jailer and priestess, kobold and cogling...
 ability.drain.name = Life drain
 ability.drain.desc = heals itself by a third of the damage it deals.
+
+# more heroes
+unit.giant = Giant
+unit.fairy = Fairy Spy
+unit.battlemage = Battle Mage
+msg.trap_wrecked = The heroes wrecked a trap: {0}.
+best.giant.text = A giant is what happens when a knight eats his vegetables for three hundred years. Slow, enormous, and it treats doors as a suggestion. | It wrecks traps simply by standing next to them. Revolting manners. Hit it with everything, preferably from afar.
+best.fairy.text = The Order's little informer: a glowing gnat with wings, sent ahead to find your traps and tell everybody. Once it has seen a trap, the heroes smash it. | It also sprinkles healing dust on the heroes. Swat it first. Twice, to be sure.
+best.battlemage.text = A mage in the Order's robes who thinks walls are a personal insult. Reinforced walls burst under his fireballs, and he never stops talking about it. | Fragile up close. Steel walls annoy him most - good.