fix: handle invalid condition tuple error

[adriantam]

Description

Fix HandleTupleValidateError so that it handles invalid condition tuple error bugs.

References

Close #1419

Testing

1. Add with the following model

model
  schema 1.1

type user

type group
  relations
    define member: [user]
    define can_access: [user with less_than_hundred]
    
condition less_than_hundred(x: int) {
  x < 100
}

Send GET with

{
    "tuple_key": {
        "user": "user:test",
        "relation": "can_access",
        "object": "group:8"
    },
    "contextual_tuples": {
        "tuple_keys": [
            {
                "user": "user:test",
                "relation": "can_access",
                "object": "group:8",
                "condition": {
                    "name": "less_than_hundred",
                    "context": {
                        "x": "b"
                    }
                }
            }
        ]
    }
}

and see 400 Bad Request error with body

{
    "code": "validation_error",
    "message": "Invalid tuple 'group:8#can_access@user:test (condition name:\"less_than_hundred\"  context:{fields:{key:\"x\"  value:{string_value:\"b\"}}})'. Reason: parameter type error on condition 'less_than_hundred' - failed to convert context parameter 'x': expected a int64 value, but found invalid string value 'b'"
}

2. With the following body

model
  schema 1.1

type user

type group
  relations
    define member: [user with restricted_to_ip]

type application
  relations
    define allowed: [group#member]

condition restricted_to_ip(allowed_ip_address: ipaddress, current_ip_address: ipaddress) {
  current_ip_address == allowed_ip_address
}

Check with body

{
    "tuple_key": {
        "user": "user:some_user",
        "relation": "allowed",
        "object": "application:test_application"
    },
    "contextual_tuples": {
        "tuple_keys": [
            {
                "user": "user:some_user",
                "relation": "member",
                "object": "group:premium"
            }
        ]
    }
}

produces 400 error with error message

{
    "code": "validation_error",
    "message": "Invalid tuple 'group:premium#member@user:some_user (condition <nil>)'. Reason: condition is missing"
}

Review Checklist

• I have clicked on "allow edits by maintainers".
• I have added documentation for new/changed functionality in this PR or in a PR to openfga.dev [Provide a link to any relevant PRs in the references section above]
• The correct base branch is being used, if not main
• I have added tests to validate that the change in functionality is working as expected