Initial commit: Theriapolis baseline at port/godot branch point

Captures the pre-Godot-port state of the codebase. This is the rollback
anchor for the Godot port (M0 of theriapolis-rpg-implementation-plan-godot-port.md).
All Phase 0 through Phase 6.5 work is included; Phase 7 is in flight.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Content/Data/room_templates/imperium/entry_grand_hall.json

@@ -0,0 +1,32 @@
+{
+  "id": "imperium.entry_grand_hall",
+  "name": "Grand Hall",
+  "type": "imperium",
+  "built_by": "imperium",
+  "size_class": "medium",
+  "roles_eligible": ["entry"],
+  "footprint_w_tiles": 12,
+  "footprint_h_tiles": 8,
+  "grid": [
+    "############",
+    "#..........#",
+    "#.P......P.#",
+    "#..........D",
+    "#....S.....#",
+    "#..........D",
+    "#.P......P.#",
+    "############"
+  ],
+  "doors": [
+    { "x": 11, "y": 3, "facing": "E" },
+    { "x": 11, "y": 5, "facing": "E" }
+  ],
+  "decos": [
+    { "x": 2, "y": 2, "deco": "pillar" },
+    { "x": 9, "y": 2, "deco": "pillar" },
+    { "x": 2, "y": 6, "deco": "pillar" },
+    { "x": 9, "y": 6, "deco": "pillar" }
+  ],
+  "narrative_text": "Four broken pillars frame a worn floor. The Imperium emblem inlaid in the centre has been chipped down to bare stone — defaced more than weathered.",
+  "weight": 1.0
+}