refactor: rename swift → cortex in code and documentation

Complete rename of "swift" terminology to "cortex" across the codebase:

Code Changes:
- Rename directories: lib/swift → lib/cortex, components/swift → components/cortex
- Rename API routes: /api/swift/* → /api/cortex/*
- Rename page routes: /epd/swift → /epd/cortex
- Rename store: swift-store.ts → cortex-store.ts

Type Renames:
- SwiftIntent → CortexIntent
- SwiftStore → CortexStore
- useSwiftStore → useCortexStore
- SwiftContext → CortexContext
- useSwiftVoice → useCortexVoice

Documentation Updates (docs/intent/):
- Safety Net → Nudge (Layer 3 rename)
- SafetySuggestion → NudgeSuggestion
- evaluateSafetyNet → evaluateNudge
- SWIFT_* feature flags → CORTEX_*
- All path references updated to match new structure

Files affected: 47 files, ~700 lines changed

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

app/api/intent/classify/route.ts

@@ -8,10 +8,10 @@
 import { createClient } from '@/lib/auth/server';
 import { NextRequest, NextResponse } from 'next/server';
 import { z } from 'zod';
-import { classifyIntent, isHighConfidence } from '@/lib/swift/intent-classifier';
-import { classifyIntentWithAI } from '@/lib/swift/intent-classifier-ai';
-import { extractEntities } from '@/lib/swift/entity-extractor';
-import type { IntentClassificationResult } from '@/lib/swift/types';
+import { classifyIntent, isHighConfidence } from '@/lib/cortex/intent-classifier';
+import { classifyIntentWithAI } from '@/lib/cortex/intent-classifier-ai';
+import { extractEntities } from '@/lib/cortex/entity-extractor';
+import type { IntentClassificationResult } from '@/lib/cortex/types';
 
 // Request schema
 const ClassifyRequestSchema = z.object({