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>

src/ui.rs

@@ -420,13 +420,21 @@ impl Ui {
         let wave_col = if g.wave_timer < 30.0 { RED } else { TXT };
         let vol = if settings.muted { tr("hud.off") } else { format!("{}%", (settings.volume * 100.0).round() as i32) };
         let mut segs: Vec<Vec<Part>> = vec![
-            vec![txt(tr("hud.gold"), GOLD), Part::Gap, txt(format!("{}/{}", g.gold as i32, g.gold_cap() as i32), TXT)],
+            vec![
+                txt(tr("hud.gold"), GOLD),
+                Part::Gap,
+                txt(format!("{}/{}", g.gold as i32, g.gold_cap() as i32), TXT),
+                Part::Gap,
+                // what the next payday costs, in red
+                txt(format!("-{}", g.next_payday_cost().ceil() as i32), RED),
+            ],
             vec![txt(tr("hud.mana"), MANA), Part::Gap, Part::Bar(g.mana / MANA_MAX, MANA), Part::Gap, txt(format!("{:<3}", g.mana as i32), TXT)],
             vec![txt(tr("hud.core"), RED), Part::Gap, Part::Bar(g.core_hp / CORE_HP, RED)],
             vec![txt(tr("hud.gate"), BLUE), Part::Gap, Part::Bar(g.gate_hp / GATE_HP, BLUE)],
             vec![txt(tr("hud.creatures"), TXT), Part::Gap, txt(format!("{}/{}", g.creature_count(), cap), TXT)],
             vec![txt(tr("hud.workers"), TXT), Part::Gap, txt(g.worker_count().to_string(), TXT)],
             vec![txt(trf("hud.wave", &[(g.wave + 1).to_string()]), wave_col), Part::Gap, txt(mmss(g.wave_timer), TXT)],
+            vec![txt(tr("hud.payday"), if g.payday <= PAYDAY_WARN { RED } else { GOLD }), Part::Gap, txt(mmss(g.payday), TXT)],
             vec![txt(tr("hud.army"), TXT), Part::Gap, txt((g.army_value() as i32).to_string(), TXT)],
         ];
         if !g.hand.is_empty() {
@@ -970,8 +978,9 @@ pub fn hover_info(g: &Game, ent: Option<usize>, tile: Option<(i32, i32)>) -> Vec
             out.push((tr("tile.reinforced_info"), DIM));
         }
         Kind::Earth => out.push((tr("tile.earth"), FRAME_HI)),
-        Kind::Gold => {
-            out.push((tr("tile.gold"), GOLD));
+        Kind::Gold | Kind::Silver | Kind::Ruby | Kind::Diamond => {
+            let key = ["tile.gold", "tile.silver", "tile.ruby", "tile.diamond"][t.vein().unwrap_or(0) as usize];
+            out.push((tr(key), GOLD));
             out.push((trf("tile.gold_amount", &[t.gold.to_string()]), GOLD));
         }
         Kind::Floor => {
@@ -1021,6 +1030,10 @@ pub fn hover_info(g: &Game, ent: Option<usize>, tile: Option<(i32, i32)>) -> Vec
                 out.push((tr(ROOM_NAMES[r]), FRAME_HI));
                 match k {
                     Kind::Farm => out.push((trf("farm.food", &[(t.food as i32).to_string()]), GREEN)),
+                    Kind::Treasury if t.gold > 0 => {
+                        let what = ["res.gold", "res.silver", "res.ruby", "res.diamond"][(t.res & 3) as usize];
+                        out.push((trf("treasury.content", &[t.gold.to_string(), tr(what)]), GOLD));
+                    }
                     Kind::Lair => out.push((tr(if t.bed != 0 { "lair.taken" } else { "lair.free" }), DIM)),
                     Kind::Torture => {
                         let used = g.ents.iter().filter(|e| e.alive && e.hero && e.captive != 0).count();