Allow the use of dots (.) in prompt variables

[vvp-trilogy]

Describe the feature or potential improvement

Langfuse does not recognize variables that contain dots in their names. For example, Record.Name is not recognized. This limitation prevents use cases where objects need to be used as input.

Production Use Case (Works)

1. A call to a REST API returns a JSON object.
2. A prompt is fetched from Langfuse, and variables are replaced using the JSON object as input. For instance, the variable {{object.prop1.prop2}} is resolved to the corresponding value within the JSON object.

Issue
It is currently not possible to use Playground and Experiments in Langfuse because prompt variables with dots in their names are not recognized.

Feature Request
Would it be possible to simplify the variable syntax and allow the use of dots within variable names?

Additional information

Somewhat related to this request: https://github.com/orgs/langfuse/discussions/4060