Wolves with a den, fishing, and a mixed diet

Wolves
- Den: a boulder cave at the foot of the rim, sited from the seed (away
  from the sea and spawn, mouth toward the valley, clearing in front)
- Grace period: no wolves days 1-2; they move in on day 3 and howl; hunting
  from night 4; pack of 2, 3 from day 6, 4 from day 9; replaced by day
- Wary pack hunters: circle and dart in one at a time; a lit campfire is a
  safe zone, a torch makes them hesitate, walls block bites (line of
  sight); hit one and the pack turns; hurt wolves flee; a lone wolf is
  timid; by day they defend the den; home at dawn
- Glowing eyes, synthesised howls, can't sleep with wolves prowling
- Wolf pelt and Wolf Cloak (+25 warmth)
- Animals take a committed detour around obstacles

Fishing
- Fishing rod (workbench); cast a float onto the lake, 1.5 s to land a bite
- Perch and rarer trout; faster bites at dawn/dusk and in rain; grill them
- Visible fish near the shore that jump with splash rings

Mixed diet
- Foods belong to meat, fish or greens; each level runs down over ~1.5 days
- One group low: no healing; two low: Malnourished (health drains);
  all three good: Balanced diet (heal x1.5); HUD diet bars; saved

Tests: test_wolves and test_fishing_diet; run_all.sh covers 9 suites

scripts/ui/pause_menu.gd

@@ -10,6 +10,7 @@ const CONTROLS := [
 	["Mouse", "Look"], ["E", "Interact / pick up / add fuel"], ["Left click", "Use tool / place"],
 	["Right click (holding food)", "Eat"], ["Right click (spear / cloak)", "Throw / wear"],
 	["Hold left click (bow)", "Draw, release to shoot"],
+	["Left click (fishing rod)", "Cast / reel in when the float dips"],
 	["R", "Rotate piece (building pieces: quarter turns)"], ["X", "Dismantle the piece you're looking at"],
 	["E on a bed", "Set spawn point / sleep (night, under a roof)"],
 	["1 - 8, wheel", "Hotbar"], ["Tab", "Inventory & crafting (shift-click Craft for 5)"],