Add support for new CrewAI Flow decorators

[Zie619]

Description

CrewAI has introduced Flow decorators for agent orchestration. Add detection for these new patterns.

Why

• CrewAI is gaining popularity (100K+ certified developers)
• Flow decorators are new and not yet fully supported
• Competitor (Agentic Radar) already has CrewAI integration

Decorators to Detect

• @flow - Defines a flow
• @start() - Marks start of flow
• @listen() - Listens for events
• @router() - Routes between flows

Example Code to Detect

from crewai.flow import Flow, start, listen, router

class MyFlow(Flow):
    @start()
    def start_method(self):
        pass

    @listen(start_method)
    def next_step(self):
        pass

Acceptance Criteria

• AST scanner detects Flow class inheritance
• Detects @start, @listen, @router decorators
• Maps flow relationships
• Tests with sample CrewAI Flow code

Labels

good first issue, enhancement, crewai