Refactor: Clean up obsolete files and organize codebase structure

This commit removes deprecated modules and reorganizes code into logical directories:

Deleted files (superseded by newer systems):
- claude_code_server.py (replaced by agent-sdk direct integration)
- heartbeat.py (superseded by scheduled_tasks.py)
- pulse_brain.py (unused in production)
- config/pulse_brain_config.py (obsolete config)

Created directory structure:
- examples/ (7 example files: example_*.py, demo_*.py)
- tests/ (5 test files: test_*.py)

Updated imports:
- agent.py: Removed heartbeat module and all enable_heartbeat logic
- bot_runner.py: Removed heartbeat parameter from Agent initialization
- llm_interface.py: Updated deprecated claude_code_server message

Preserved essential files:
- hooks.py (for future use)
- adapters/skill_integration.py (for future use)
- All Google integration tools (Gmail, Calendar, Contacts)
- GLM provider code (backward compatibility)

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

README.md

@@ -15,12 +15,13 @@ A lightweight, cost-effective AI agent framework for building proactive bots wit
 
 ## Features
 
+- **Flexible Claude Integration**: Use Pro subscription OR pay-per-token API via Agent SDK (no server needed)
 - **Cost-Optimized AI**: Default Haiku 4.5 model (12x cheaper), auto-caching on Sonnet (90% savings), dynamic model switching
-- **Smart Memory System**: SQLite-based memory with automatic context retrieval and FTS search
+- **Smart Memory System**: SQLite-based memory with automatic context retrieval and hybrid vector search
 - **Multi-Platform Adapters**: Run on Slack, Telegram, and more simultaneously
+- **15 Integrated Tools**: File ops, shell commands, Gmail, Google Calendar, Contacts
 - **Pulse & Brain Monitoring**: 92% cost savings with intelligent conditional monitoring (recommended)
 - **Task Scheduling**: Cron-like scheduled tasks with flexible cadences
-- **Tool Use System**: File operations, command execution, and autonomous task completion
 - **Multi-LLM Support**: Claude (Anthropic) primary, GLM (z.ai) optional
 
 ## Quick Start