feat: Simplify architecture with Cortex orchestrator and clear augmentation tiers

## Major Architecture Improvements

### Cortex Refactoring
- Renamed AugmentationPipeline → Cortex for clarity
- Cortex is now the central orchestrator (not an augmentation)
- NeuralImport remains as the AI-powered SENSE augmentation
- Clean brain metaphor: BrainyData → Cortex → Augmentations

### Four-Tier Augmentation System
1. **Built-in** (Free, MIT): Neural Import, basic storage, search
2. **Community** (Free, npm): Community-created augmentations
3. **Premium** ($49-299/mo): AI Memory, Agent Coordinator, Enterprise connectors
4. **Brain Cloud** ($19-99/mo): Managed service with all features

### Zero Configuration Philosophy
- Everything works out of the box - no config needed
- Automatic model detection and loading
- Seamless integration between tiers
- Brain Cloud connects with one command: `brainy cloud`

### Documentation Updates
- Added PHILOSOPHY.md outlining design principles
- Created AUGMENTATION_ARCHITECTURE.md with tier system
- Added CLI_AUGMENTATION_GUIDE.md for augmentation management
- Updated README to "sell first" with concrete use cases
- Improved documentation organization in /docs

### Developer Experience
- Backward compatibility maintained with exports
- Clean, simple API surface
- Interactive-by-default approach
- Premium features integrate seamlessly

### Removed
- Deleted demo directory and deploy workflow (moved to website)
- Removed test wrapper scripts (bash 2>&1 bug workaround)

This refactor makes Brainy incredibly powerful yet easy to use, with everything automated and no configuration required. The Brain Cloud augmentations (AI memory, sync, coordination) integrate seamlessly as our killer features.

src/cortex.ts

@@ -0,0 +1,36 @@
+/**
+ * Cortex - The Brain's Central Orchestration System
+ * 
+ * 🧠⚛️ The cerebral cortex that coordinates all augmentations
+ * 
+ * This is the main export for the Cortex system. It provides the central
+ * coordination for all augmentations, managing their registration, execution,
+ * and pipeline orchestration.
+ */
+
+// Re-export from augmentationPipeline (which contains the Cortex class)
+export { 
+  Cortex,
+  cortex,
+  ExecutionMode,
+  PipelineOptions,
+  // Backward compatibility
+  AugmentationPipeline,
+  augmentationPipeline
+} from './augmentationPipeline.js'
+
+// Re-export augmentation types for convenience
+export type {
+  BrainyAugmentations,
+  IAugmentation,
+  ISenseAugmentation,
+  IConduitAugmentation,
+  ICognitionAugmentation,
+  IMemoryAugmentation,
+  IPerceptionAugmentation,
+  IDialogAugmentation,
+  IActivationAugmentation,
+  IWebSocketSupport,
+  AugmentationResponse,
+  AugmentationType
+} from './types/augmentations.js'