Update deprecated @session decorator references to @trace in v2 documentation

[devin-ai-integration[bot]]

Problem

The v2 documentation still contains references to the deprecated @session decorator, which should be replaced with @trace.

Files to Update

• docs/v2/concepts/decorators.mdx
• docs/v2/concepts/spans.mdx
• docs/v2/usage/tracking-agents.mdx

Changes Needed

• Update decorator table to show @trace instead of @session
• Update all code examples to use @trace
• Update text descriptions to reference trace instead of session
• Ensure migration guidance is clear

Context

The @session decorator is deprecated but maintained for backward compatibility. New documentation should consistently use @trace as the recommended approach.

Assignee

Please assign to Dwij when creating