fix(tracing): resolve OpenTelemetry warnings and token type error

[Malagurti]

Description

• Fix try_get_openai_tokens method indentation causing AttributeError
• Convert all token values to float type to resolve OpenTelemetry warnings
• Improve error handling in token collection methods
• Add safe type conversion for dictionary and None values
• Ensure consistent numeric values for all token fields
• Fix token inheritance between parent/child spans

Fixes: #3880 #3888

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Testing Guidelines

• Pull request includes test coverage for the included changes.

[Malagurti]

@microsoft-github-policy-service agree