fix: remove dead model config code for true zero-config

- Remove unused model.type validation that caused Workshop error
- Remove model config from BrainyConfig type (never used)
- Simplify modelAutoConfig.ts (always Q8 WASM)
- Clean up zeroConfig.ts model references

This fixes the "Invalid model type: balanced" error and removes
unnecessary configuration options that did nothing.

src/config/modelAutoConfig.ts

@@ -1,49 +1,24 @@
 /**
- * Model Configuration Auto-Selection
- * Always uses Q8 for optimal size/performance balance (99% accuracy, 75% smaller)
+ * Model Configuration
+ * Brainy uses Q8 WASM embeddings - no configuration needed (zero-config)
  */
 
 import { isBrowser, isNode } from '../utils/environment.js'
 
-export type ModelPrecision = 'q8'
-export type ModelPreset = 'small' | 'auto'
-
 interface ModelConfigResult {
-  precision: ModelPrecision
+  precision: 'q8'
   reason: string
   autoSelected: boolean
 }
 
 /**
- * Auto-select model precision - Always returns Q8
- * Q8 provides 99% accuracy with 75% smaller size
- * @param override - For backward compatibility, ignored
+ * Get model precision configuration
+ * Always returns Q8 - the optimal balance of size and accuracy
  */
-export function autoSelectModelPrecision(override?: ModelPrecision | ModelPreset): ModelConfigResult {
-  // Always use Q8 regardless of override for simplicity
-  // Q8 is optimal: 33MB vs 130MB, 99% accuracy retained
-  
-  // Log deprecation notice if FP32 was requested
-  if (typeof override === 'string' && override.toLowerCase().includes('fp32')) {
-    console.log('Note: FP32 precision is deprecated. Using Q8 (99% accuracy, 75% smaller).')
-  }
-  
+export function getModelPrecision(): ModelConfigResult {
   return {
     precision: 'q8',
-    reason: 'Q8 precision (99% accuracy, 75% smaller)',
-    autoSelected: true
-  }
-}
-
-/**
- * Automatically detect the best model precision for the environment
- * DEPRECATED: Always returns Q8 now
- */
-function autoDetectBestPrecision(): ModelConfigResult {
-  // Always return Q8 - deprecated function kept for backward compatibility
-  return {
-    precision: 'q8',
-    reason: 'Q8 precision (99% accuracy, 75% smaller)',
+    reason: 'Q8 WASM (23MB bundled, no downloads)',
     autoSelected: true
   }
 }
@@ -53,7 +28,7 @@ function autoDetectBestPrecision(): ModelConfigResult {
  */
 function isServerlessEnvironment(): boolean {
   if (!isNode()) return false
-  
+
   return !!(
     process.env.AWS_LAMBDA_FUNCTION_NAME ||
     process.env.VERCEL ||
@@ -65,104 +40,42 @@ function isServerlessEnvironment(): boolean {
 }
 
 /**
- * Get available memory in MB
- */
-function getAvailableMemoryMB(): number {
-  if (isBrowser()) {
-    // @ts-ignore - navigator.deviceMemory is experimental
-    if (navigator.deviceMemory) {
-      // @ts-ignore
-      return navigator.deviceMemory * 1024 // Device memory in GB
-    }
-    return 256 // Conservative default for browsers
-  }
-  
-  if (isNode()) {
-    try {
-      // Try to get memory info synchronously for Node.js
-      // This will be available in Node.js environments
-      if (typeof process !== 'undefined' && process.memoryUsage) {
-        // Use RSS (Resident Set Size) as a proxy for available memory
-        const rss = process.memoryUsage().rss
-        // Assume we can use up to 4GB or 50% more than current usage
-        return Math.min(4096, Math.floor(rss / (1024 * 1024) * 1.5))
-      }
-    } catch {
-      // Fall through to default
-    }
-    return 1024 // Default 1GB for Node.js
-  }
-  
-  return 512 // Conservative default
-}
-
-/**
- * Convenience function to check if models need to be downloaded
- * This replaces the need for BRAINY_ALLOW_REMOTE_MODELS
+ * Check if models need to be downloaded
+ * With bundled WASM model, this is rarely needed
  */
 export function shouldAutoDownloadModels(): boolean {
-  // Always allow downloads unless explicitly disabled
-  // This eliminates the need for BRAINY_ALLOW_REMOTE_MODELS
+  // Model is bundled - no downloads needed in normal operation
+  // This flag exists for edge cases only
   const explicitlyDisabled = process.env.BRAINY_ALLOW_REMOTE_MODELS === 'false'
-  
-  if (explicitlyDisabled) {
-    console.warn('Model downloads disabled via BRAINY_ALLOW_REMOTE_MODELS=false')
-    return false
-  }
-  
-  // In production, always allow downloads for seamless operation
-  if (process.env.NODE_ENV === 'production') {
-    return true
-  }
-  
-  // In development, allow downloads with a one-time notice
-  if (process.env.NODE_ENV === 'development') {
-    return true
-  }
-  
-  // Default: allow downloads
-  return true
+  return !explicitlyDisabled
 }
 
 /**
- * Get the model path with intelligent defaults
- * This replaces the need for BRAINY_MODELS_PATH env var
+ * Get the model path
+ * With bundled WASM model, this points to the package assets
  */
 export function getModelPath(): string {
-  // Check if user explicitly set a path (keeping this for advanced users)
+  // Check if user explicitly set a path (for advanced users)
   if (process.env.BRAINY_MODELS_PATH) {
     return process.env.BRAINY_MODELS_PATH
   }
-  
-  // Browser - use cache API or IndexedDB (handled by transformers.js)
+
+  // Browser - use cache API or IndexedDB
   if (isBrowser()) {
     return 'browser-cache'
   }
-  
+
   // Serverless - use /tmp for ephemeral storage
   if (isServerlessEnvironment()) {
     return '/tmp/.brainy/models'
   }
-  
+
   // Node.js - use home directory for persistent storage
   if (isNode()) {
-    // Use process.env.HOME as a fallback
     const homeDir = process.env.HOME || process.env.USERPROFILE || '~'
     return `${homeDir}/.brainy/models`
   }
-  
+
   // Fallback
   return './.brainy/models'
 }
-
-/**
- * Log model configuration decision (only in verbose mode)
- */
-export function logModelConfig(config: ModelConfigResult, verbose: boolean = false): void {
-  if (!verbose && process.env.NODE_ENV === 'production') {
-    return // Silent in production unless verbose
-  }
-  
-  const icon = config.autoSelected ? '🤖' : '👤'
-  console.log(`${icon} Model: ${config.precision.toUpperCase()} - ${config.reason}`)
-}