Fix sorting bug in validationUtils and add cache cap to AssetLoader

- validationUtils: unsorted x values now actually sorted (was returning false)
- validationUtils: duplicate x values now actually removed (was returning false)
- validationUtils: areNumbers check no longer skipped after sort/dedup
- AssetLoader: add maxCacheSize (default 100) with LRU-style eviction

Closes #21, closes #24

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

datasets/assetData/curves/index.js

@@ -2,10 +2,11 @@ const fs = require('fs');
 const path = require('path');
 
 class AssetLoader {
-  constructor() {
+  constructor(maxCacheSize = 100) {
     this.relPath = './'
     this.baseDir = path.resolve(__dirname, this.relPath);
-    this.cache = new Map(); // Cache loaded JSON files for better performance
+    this.cache = new Map();
+    this.maxCacheSize = maxCacheSize;
   }
 
   /**
@@ -46,7 +47,11 @@ class AssetLoader {
       const rawData = fs.readFileSync(filePath, 'utf8');
       const assetData = JSON.parse(rawData);
       
-      // Cache the result
+      // Cache the result (evict oldest if at capacity)
+      if (this.cache.size >= this.maxCacheSize) {
+        const oldestKey = this.cache.keys().next().value;
+        this.cache.delete(oldestKey);
+      }
       this.cache.set(cacheKey, assetData);
       
       return assetData;