v2: add 26B + 31B model tests (Phase 3)

Tests/Manifest.json

@@ -31,7 +31,23 @@
       "memory_gb": 6,
       "gpu": true,
       "model": "E4B-MarkBase",
-      "timeout_seconds": 120,
+      "timeout_seconds": 180,
+      "schedule": "on_demand"
+    },
+    "01_Model/Model26BTest.swift": {
+      "tier": 1,
+      "memory_gb": 20,
+      "gpu": true,
+      "model": "gemma-4-26b-standard",
+      "timeout_seconds": 300,
+      "schedule": "on_demand"
+    },
+    "01_Model/Model31BTest.swift": {
+      "tier": 1,
+      "memory_gb": 22,
+      "gpu": true,
+      "model": "gemma-4-31b-it-4bit",
+      "timeout_seconds": 360,
       "schedule": "on_demand"
     }
   },
@@ -86,13 +102,13 @@
     },
     "gemma-4-12b-it-4bit": {
       "path": "models/gemma-4-12b-it-4bit",
-      "format": "unknown",
+      "format": "markbase-4bit",
       "params": "12B",
-      "weight_gb": 0.008,
-      "memory_gb": 0,
+      "weight_gb": 10,
+      "memory_gb": 14,
       "multimodal": true,
-      "status": "unavailable",
-      "notes": "Corrupted/incomplete files (8KB only). Full 4-bit 12B needed."
+      "status": "available",
+      "notes": "Multimodal - text-only output saturates softcap (gibberish). Full model files (blobs) present."
     },
     "12B-it-MLX-8bit": {
       "path": "models/12B-it-MLX-8bit",