fix: persist admin runtime constants to DB across restarts

Constants were purely in-memory; any server restart reverted them
to code defaults. Now saved to metadata table as JSON on every
autosave and restored on startup.

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

server/src/config/runtimeConstants.ts

@@ -46,6 +46,15 @@ export function createRuntimeConstants() {
     getDefaults(): TunableConstants {
       return { ...DEFAULTS };
     },
+
+    /** Load saved overrides, ignoring any unknown keys */
+    loadOverrides(overrides: Partial<TunableConstants>): void {
+      for (const [key, value] of Object.entries(overrides)) {
+        if (key in DEFAULTS && typeof value === 'number') {
+          current[key as TunableKey] = value;
+        }
+      }
+    },
   };
 }
 

server/src/game/GameLoop.ts

@@ -110,7 +110,7 @@ export class GameLoop {
         obstacles: new Set(this.map.getObstacles().map(p => `${p.x},${p.y}`)),
         foodPositions: this.map.getPointsOfInterest('food').map(p => p.position),
       });
-      this.saveManager.saveEntityState(this.world, 0);
+      this.saveManager.saveEntityState(this.world, 0, this.runtimeConstants);
       this.wirePersistenceCallbacks();
     }
     console.log('Created new world');
@@ -127,7 +127,7 @@ export class GameLoop {
     this.world.setSingleton('recipeRegistry', RecipeRegistry.createDefault());
 
     // Load entities (also restores bondRegistry singleton)
-    this.tick = this.saveManager!.loadEntityState(this.world);
+    this.tick = this.saveManager!.loadEntityState(this.world, this.runtimeConstants);
 
     // Create and load inventionTimeline
     const inventionTimeline = createInventionTimeline();
@@ -273,7 +273,7 @@ export class GameLoop {
     this.saveInterval = setInterval(() => {
       if (this.saveManager) {
         try {
-          this.saveManager.saveEntityState(this.world, this.tick);
+          this.saveManager.saveEntityState(this.world, this.tick, this.runtimeConstants);
           this.logService.log('info', 'Save', `Autosaved at tick ${this.tick}`);
         } catch (err) {
           this.logService.log('error', 'Save', `Autosave failed: ${(err as Error).message}`);
@@ -294,7 +294,7 @@ export class GameLoop {
     }
     // Final save on shutdown
     if (this.saveManager) {
-      this.saveManager.saveEntityState(this.world, this.tick);
+      this.saveManager.saveEntityState(this.world, this.tick, this.runtimeConstants);
       this.saveManager.close();
       console.log(`Final save at tick ${this.tick}`);
     }

server/src/persistence/saveManager.ts

@@ -1,9 +1,10 @@
 import fs from 'fs';
 import { openDatabase, closeDatabase, getDatabase, getSchemaVersion, CURRENT_SCHEMA_VERSION } from './database.js';
-import { saveTiles, loadTiles, saveMetadata, loadMetadata, type TileData } from './worldSerializer.js';
+import { saveTiles, loadTiles, saveMetadata, loadMetadata, saveRuntimeConstants, loadRuntimeConstants, type TileData } from './worldSerializer.js';
 import { saveEntities, loadEntities } from './entitySerializer.js';
 import type { World } from '../ecs/World.js';
 import type { GameMap } from '../map/GameMap.js';
+import type { RuntimeConstants } from '../config/runtimeConstants.js';
 
 export class SaveManager {
   private filepath: string;
@@ -92,16 +93,25 @@ export class SaveManager {
     return true;
   }
 
-  /** Save all entity state (entities, components, relationships, bonds) + metadata */
-  saveEntityState(world: World, tick: number): void {
+  /** Save all entity state (entities, components, relationships, bonds) + metadata + runtime constants */
+  saveEntityState(world: World, tick: number, runtimeConstants?: RuntimeConstants): void {
     saveEntities(world);
     saveMetadata({ tick, lastSavedAt: new Date().toISOString() });
+    if (runtimeConstants) {
+      saveRuntimeConstants(runtimeConstants.getAll());
+    }
   }
 
-  /** Load entity state into world. Returns saved tick number. */
-  loadEntityState(world: World): number {
+  /** Load entity state into world. Restores runtime constants if saved. Returns saved tick number. */
+  loadEntityState(world: World, runtimeConstants?: RuntimeConstants): number {
     loadEntities(world);
     const meta = loadMetadata();
+    if (runtimeConstants) {
+      const saved = loadRuntimeConstants();
+      if (saved) {
+        runtimeConstants.loadOverrides(saved);
+      }
+    }
     return meta.tick;
   }
 

server/src/persistence/worldSerializer.ts

@@ -114,3 +114,22 @@ export function loadMetadata(): { tick: number; lastSavedAt: string } {
 
   return { tick, lastSavedAt };
 }
+
+export function saveRuntimeConstants(constants: Record<string, number>): void {
+  const db = getDatabase();
+  const upsert = db.prepare(
+    "INSERT INTO metadata (key, value) VALUES (?, ?) ON CONFLICT(key) DO UPDATE SET value = excluded.value"
+  );
+  upsert.run('runtime_constants', JSON.stringify(constants));
+}
+
+export function loadRuntimeConstants(): Record<string, number> | null {
+  const db = getDatabase();
+  const row = db.prepare("SELECT value FROM metadata WHERE key = 'runtime_constants'").get() as { value: string } | undefined;
+  if (!row) return null;
+  try {
+    return JSON.parse(row.value);
+  } catch {
+    return null;
+  }
+}