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Deleted files (superseded by newer systems):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- heartbeat.py (superseded by scheduled_tasks.py)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>

bot_runner.py

@@ -77,7 +77,6 @@ class BotRunner:
         self.agent = Agent(
             provider="claude",
             workspace_dir="./memory_workspace",
-            enable_heartbeat=False,
         )
         print("[Setup] Agent initialized")