fix: make guardian names deterministic per floor instead of using Math.random()

- generateGuardianName() now takes a floor parameter and uses floor % prefixes.length for deterministic prefix selection
- generateComboGuardianName() now takes a floor parameter and uses (floor + i) % prefixes.length for each element
- getGuardianForFloor() passes floor to generateGuardianName for static guardians with empty names
- getExtendedGuardian() passes floor to generateComboGuardianName for combo guardians
- Removes dependency on Math.random() → names are stable across ticks/refreshes

Fixes #161

docs/circular-deps.txt

@@ -1,4 +1,4 @@
 # Circular Dependencies
-Generated: 2026-05-27T09:16:38.657Z
+Generated: 2026-05-27T09:18:37.387Z
 
 No circular dependencies found. ✅

docs/dependency-graph.json

@@ -1,6 +1,6 @@
 {
   "_meta": {
-    "generated": "2026-05-27T09:16:36.915Z",
+    "generated": "2026-05-27T09:18:35.464Z",
     "description": "Import dependency graph for src/lib/game. Keys are files, values are arrays of files they import.",
     "usage": "To find what a file affects, search for its path in the VALUES. To find what a file depends on, look at its KEY entry."
   },

docs/project-structure.txt

@@ -213,6 +213,7 @@ Mana-Loop/
 │       │   │   ├── floor-utils.test.ts
 │       │   │   ├── floor-utils.upgraded.test.ts
 │       │   │   ├── formatting.test.ts
+│       │   │   ├── guardian-names.test.ts
 │       │   │   ├── mana-utils.test.ts
 │       │   │   ├── pact-utils.test.ts
 │       │   │   ├── regression-fixes.test.ts