Silver, ruby and diamond veins; treasury shows its treasures; announced payday

- New veins (appended kinds): silver (common), ruby (rare), diamond (very rare, far from the core);
  treasure caves contain gems; each treasure is worth a different amount per strike and per vein
- Imps carry one kind of treasure at a time
- Treasury tiles hold up to 500 each and show gold coins, silver bars, rubies or diamonds;
  spending empties random treasury tiles, the soul core keeps what does not fit
- Training no longer drains gold continuously: it is billed on the next payday
- Payday is announced 20 s before (message with the cost); the HUD shows a payday countdown and
  the cost of the next payday in red next to the gold counter
- Tests for the treasury and the payday bill

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

lang/de.lang

@@ -180,7 +180,7 @@ tile.rock = Fels
 tile.indestructible = unzerstörbar
 tile.earth = Erde
 tile.gold = Goldader
-tile.gold_amount = {0} Gold
+tile.gold_amount = Wert: {0} Gold
 tile.floor = Boden
 owner.player = erobert
 owner.hero = Heldengebiet
@@ -401,3 +401,16 @@ tile.bridge = Holzbrücke
 tile.lavabridge = Steinbrücke
 tile.shard = Splitter deines Seelenkerns
 tile.shard_info = Erobere diese Kammer, um den Splitter zurückzuholen.
+
+# treasures and payday
+tile.silver = Silberader
+tile.ruby = Rubinader
+tile.diamond = Diamantader
+res.gold = Gold
+res.silver = Silber
+res.ruby = Rubinen
+res.diamond = Diamanten
+treasury.content = Enthält {0} in {1}
+hud.payday = Zahltag
+msg.payday_soon = Zahltag in {0} Sekunden: Deine Kreaturen wollen {1} Gold.
+hint.payday_short = Für den nächsten Zahltag reicht das Gold nicht. Unbezahlte Kreaturen werden wütend!

lang/en.lang

@@ -181,7 +181,7 @@ tile.rock = Rock
 tile.indestructible = indestructible
 tile.earth = Earth
 tile.gold = Gold Vein
-tile.gold_amount = {0} gold
+tile.gold_amount = Worth {0} gold
 tile.floor = Floor
 owner.player = claimed
 owner.hero = hero territory
@@ -402,3 +402,16 @@ tile.bridge = Wooden bridge
 tile.lavabridge = Stone bridge
 tile.shard = Shard of your soul core
 tile.shard_info = Claim this chamber to take the shard back.
+
+# treasures and payday
+tile.silver = Silver vein
+tile.ruby = Ruby vein
+tile.diamond = Diamond vein
+res.gold = gold
+res.silver = silver
+res.ruby = rubies
+res.diamond = diamonds
+treasury.content = Holds {0} worth of {1}
+hud.payday = Payday
+msg.payday_soon = Payday in {0} seconds: your creatures want {1} gold.
+hint.payday_short = There is not enough gold for the coming payday. Unpaid creatures get angry!