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

tests/run_all.sh

@@ -4,7 +4,7 @@
 # Usage: tests/run_all.sh   (from the repo root; needs `godot` on PATH)
 cd "$(dirname "$0")/.." || exit 1
 status=0
-for t in test_survival_core test_survival_stats test_save_load test_weather_building test_creatures_combat test_terrain_edges test_boundary; do
+for t in test_survival_core test_survival_stats test_save_load test_weather_building test_creatures_combat test_wolves test_fishing_diet test_terrain_edges test_boundary; do
 	extra=""
 	[ "$t" = "test_boundary" ] && extra="--fixed-fps 30"
 	# A suite that waits on a world that failed to load would hang forever,