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

data/recipes.json

@@ -185,6 +185,46 @@
         "hide": 4,
         "fiber": 4
       }
+    },
+    {
+      "id": "wolf_cloak",
+      "output": "wolf_cloak",
+      "count": 1,
+      "station": "workbench",
+      "inputs": {
+        "wolf_pelt": 3,
+        "hide": 2,
+        "fiber": 4
+      }
+    },
+    {
+      "id": "fishing_rod",
+      "output": "fishing_rod",
+      "count": 1,
+      "station": "workbench",
+      "inputs": {
+        "stick": 2,
+        "fiber": 3,
+        "flint": 1
+      }
+    },
+    {
+      "id": "grilled_perch",
+      "output": "grilled_perch",
+      "count": 1,
+      "station": "campfire",
+      "inputs": {
+        "perch": 1
+      }
+    },
+    {
+      "id": "grilled_trout",
+      "output": "grilled_trout",
+      "count": 1,
+      "station": "campfire",
+      "inputs": {
+        "trout": 1
+      }
     }
   ]
 }