refactor(jans-cedarling): enhance schema parser and entity creation implementation

[rmarinn]

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Description

This PR refactors the JSON schema struct and the Cedar entity-building logic to improve code readability and maintainability.

Target issue

target issue: #10513

closes #10513

Implementation Details

1. Introduction of EntityBuilder Struct

   • A new EntityBuilder struct encapsulates configuration and logic for creating entities.
   • This improves modularity, making the entity-building process more self-contained and easier to use across the codebase.
   • Also fixes fix(jans-cedarling): error during creating entity of type record #10545

2. Refactoring CedarSchemaJson

   • The CedarSchemaJson struct has been redesigned for better usability.
   • Deserialization and JSON schema parsing logic is now self-contained, reducing complexity for other callers.

3. Unit Tests

   • Added unit tests for the refactored components.
   • Future test cases will be easier to implement due to reduced coupling and improved struct/function design.

4. Improved Automatically adding entities to the context

   • We don't need to do the "lower_snake_case convention" for entity names anymore to automatically add them to the context.

Entity Builder

The EntityBuilder struct centralizes entity creation logic and holds configuration on initialization.

Usage:

pub struct EntityBuilder {
    schema: CedarSchemaJson,
    entity_names: EntityNames,
    build_workload: bool,
    build_user: bool,
}

Function implementations on this struct will have the entity creation code. Other modules will only have to use these functions.

impl EntityBuilder {
    pub fn new(
        schema: CedarSchemaJson,
        entity_names: EntityNames,
        build_workload: bool,
        build_user: bool,
    ) -> Self {
        // ...
    }

    pub fn build_entities(
        &self,
        tokens: &DecodedTokens,
        resource: &ResourceData,
    ) -> Result<AuthorizeEntitiesData, BuildCedarlingEntityError> {
        // ...
    }
}

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Test and Document the changes

• Static code analysis has been run locally and issues have been fixed
• Relevant unit and integration tests have been added/updated
• Relevant documentation has been updated if any (i.e. user guides, installation and configuration guides, technical design docs etc)

Please check the below before submitting your PR. The PR will not be merged if there are no commits that start with docs: to indicate documentation changes or if the below checklist is not selected.

• I confirm that there is no impact on the docs due to the code changes in this PR.

[rmarinn]

I had to resolve merge conflicts with the WASM PR so could you re-review @olehbozhok

[djellemah]

(regex_mapping.cedar_policy_type == type_name).then_some((claim_name, mapping))

is quite a nice way to do it.

[rmarinn]

fixed here bd58549

[djellemah]

I'm not clear whether or not serde is inadequate to parse the json schema files. But it seems others are waiting for this PR.

[rmarinn]

I'm not clear whether or not serde is inadequate to parse the json schema files. But it seems others are waiting for this PR.

I'm not sure what you mean. I did used serde to parse the json schema files -- though we needed to add some since just because it's a valid json it doesn't mean that it's a valid schema as described in the cedar policy docs.