fix(terraform): correctly add edge from output to source

[eshmayovitz]

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Description

Fixed a bug in Checkov's Terraform graph builder where cross-module resource connections were not detected when resources reference each other through module outputs.

Problem: When a resource (e.g., aws_dynamodb_resource_policy) references another resource (e.g., aws_dynamodb_table) via a module output (e.g., module.dynamodb.table_arn), Checkov's graph builder created an edge to the OUTPUT block but failed to trace the output's value back to the actual source resource. This caused connection-based security checks to fail incorrectly.

Fix

Added _trace_output_to_source_resource() method in checkov/terraform/graph_builder/local_graph.py that:

Checklist:

• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• I have added tests that prove my feature, policy, or fix is effective and works
• New and existing tests pass locally with my changes