[Py]Prompt Parsing and Rendering

[tanyasingh1902]

Implement parse method.
Parse a prompt template string into a ParsedPrompt object using the parseDocument function from the parse module.

Implement render method.
Take a prompt template, data, and options as input.
Call compile to get a rendering function.
Execute the rendering function and return the result.

Implement compile method.
Take a prompt template (string or ParsedPrompt) and optional metadata.
Resolve partials.
Compile the Handlebars template.
Create and return a rendering function that fills in variables and applies transformations.