Issue:
Bug: [BUG] (connector): [Netcetera]  Fix three_ds_requestor_challenge_ind field in Netcetera Response



### Bug Description

Currently we are not recieving field **_three_ds_requestor_challenge_ind_** in Netcetera's authentication response since the struct is incorrectly declared in the transformers file. 
1. **_three_ds_requestor_challenge_ind_** is currently a part of _**NetceteraAuthenticationSuccessResponse**_ enum, but it should be a field inside authenitcation request
2. **_three_ds_requestor_challenge_ind_** has type optional string, whereas it is vector of string (ref documentation - https://3dss.netcetera.com/3dsserver/doc/2.5.2.1/3ds-authentication) 

**Current structure**
```
NetceteraAuthenticationSuccessResponse{
....
three_ds_requestor_challenge_ind: Option<String>
...}

```

**Correct structure**
```
NetceteraAuthenticationSuccessResponse{
....
authentication_request: {
three_ds_requestor_challenge_ind: Option<Vector<String>>,
}
...}

```


### Expected Behavior

When the struct is fixed in code, expected behavior is to recieve **three_ds_requestor_challenge_ind** field in  Netcetera's authentication response.

**correct structure**
```
NetceteraAuthenticationSuccessResponse{
....
authentication_request: {
three_ds_requestor_challenge_ind: Option<Vector<String>>,
}
...}

```


### Actual Behavior

Currently we are not recieving field **_three_ds_requestor_challenge_ind_** in Netcetera's authentication response since the struct is incorrect, and as a result sending challengeCode as null to Cybersource

### Steps To Reproduce

Provide an unambiguous set of steps to reproduce this bug. Include code or configuration to reproduce, if relevant.
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### Context For The Bug

_No response_

### Environment

Are you using hyperswitch hosted version? Yes/No
If yes, please provide the value of the `x-request-id` response header to help us debug your issue.

If not (or if building/running locally), please provide the following details:
1. Operating System or Linux distribution:
2. Rust version (output of `rustc --version`): ``
3. App version (output of `cargo r --features vergen -- --version`): ``


### Have you spent some time checking if this bug has been raised before?

- [x] I checked and didn't find a similar issue

### Have you read the Contributing Guidelines?

- [x] I have read the [Contributing Guidelines](https://github.com/juspay/hyperswitch/blob/main/docs/CONTRIBUTING.md)

### Are you willing to submit a PR?

Yes, I am willing to submit a PR!

Pull request description:
## Type of Change
<!-- Put an `x` in the boxes that apply -->

- [ ] Bugfix
- [ ] New feature
- [ ] Enhancement
- [ ] Refactoring
- [ ] Dependency updates
- [ ] Documentation
- [ ] CI/CD

## Description
Currently we are not recieving field **_three_ds_requestor_challenge_ind_** in Netcetera's authentication response since the struct is incorrectly declared in the transformers file.

1. **_three_ds_requestor_challenge_ind_** is currently a part of _**NetceteraAuthenticationSuccessResponse**_ enum, but it should be a field inside **_authenitcation_request_**
2. **_three_ds_requestor_challenge_ind_** has type optional string currently, but it should be a vector of string (ref documentation - https://3dss.netcetera.com/3dsserver/doc/2.5.2.1/3ds-authentication) 

**Current structure**
```
NetceteraAuthenticationSuccessResponse{
....
three_ds_requestor_challenge_ind: Option<String>
...}

```

**Correct structure**
```
NetceteraAuthenticationSuccessResponse{
....
authentication_request: {
three_ds_requestor_challenge_ind: Option<Vector<String>>,
}
...}

```
This PR introduces the above fix in the struct.



### Additional Changes

- [ ] This PR modifies the API contract
- [ ] This PR modifies the database schema
- [ ] This PR modifies application configuration/environment variables

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1. `config`
2. `crates/router/src/configs`
3. `loadtest/config`
-->


## Motivation and Context
<!--
Why is this change required? What problem does it solve?
If it fixes an open issue, please link to the issue here.

If you don't have an issue, we'd recommend starting with one first so the PR
can focus on the implementation (unless it is an obvious bug or documentation fix
that will have little conversation).
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## How did you test it?
<!--
Did you write an integration/unit/API test to verify the code changes?
Or did you test this change manually (provide relevant screenshots)?
-->
Tested netcetera's challenge via local hyperswitch sdk.
As expected, we are now able to get **_three_ds_requestor_challenge_ind_** field in the NetceteraAuthenticationSuccessResponse.

<img width="2560" height="135" alt="Screenshot 2025-08-06 at 4 29 03 PM" src="https://github.com/user-attachments/assets/45fee6c0-b785-4f3e-abb2-0d74468d2024" />


## Checklist
<!-- Put an `x` in the boxes that apply -->


- [x] I formatted the code `cargo +nightly fmt --all`
- [X] I addressed lints thrown by `cargo clippy`
- [x] I reviewed the submitted code
- [ ] I added unit tests for my changes where possible


Testing:

Tested netcetera's challenge via local hyperswitch sdk.
As expected, we are now able to get **_three_ds_requestor_challenge_ind_** field in the NetceteraAuthenticationSuccessResponse.

<img width="2560" height="135" alt="Screenshot 2025-08-06 at 4 29 03 PM" src="https://github.com/user-attachments/assets/45fee6c0-b785-4f3e-abb2-0d74468d2024" />

Patch:
diff --git a/crates/hyperswitch_connectors/src/connectors/netcetera/transformers.rs b/crates/hyperswitch_connectors/src/connectors/netcetera/transformers.rs
index fc334d68167..01189f6b926 100644
--- a/crates/hyperswitch_connectors/src/connectors/netcetera/transformers.rs
+++ b/crates/hyperswitch_connectors/src/connectors/netcetera/transformers.rs
@@ -158,6 +158,13 @@ impl
                     }
                     Some(ACSChallengeMandatedIndicator::N) | None => AuthNFlowType::Frictionless,
                 };
+
+                let challenge_code = response
+                    .authentication_request
+                    .as_ref()
+                    .and_then(|req| req.three_ds_requestor_challenge_ind.as_ref())
+                    .and_then(|v| v.first().cloned());
+
                 Ok(AuthenticationResponseData::AuthNResponse {
                     authn_flow_type,
                     authentication_value: response.authentication_value,
@@ -165,7 +172,7 @@ impl
                     connector_metadata: None,
                     ds_trans_id: response.authentication_response.ds_trans_id,
                     eci: response.eci,
-                    challenge_code: response.three_ds_requestor_challenge_ind,
+                    challenge_code,
                     challenge_cancel: response.challenge_cancel,
                     challenge_code_reason: response.trans_status_reason,
                     message_extension: response.message_extension.and_then(|v| {
@@ -653,13 +660,12 @@ pub struct NetceteraAuthenticationSuccessResponse {
     pub authentication_value: Option<Secret<String>>,
     pub eci: Option<String>,
     pub acs_challenge_mandated: Option<ACSChallengeMandatedIndicator>,
+    pub authentication_request: Option<AuthenticationRequest>,
     pub authentication_response: AuthenticationResponse,
     #[serde(rename = "base64EncodedChallengeRequest")]
     pub encoded_challenge_request: Option<String>,
     pub challenge_cancel: Option<String>,
     pub trans_status_reason: Option<String>,
-    #[serde(rename = "threeDSRequestorChallengeInd")]
-    pub three_ds_requestor_challenge_ind: Option<String>,
     pub message_extension: Option<Vec<MessageExtensionAttribute>>,
 }
 
@@ -669,6 +675,13 @@ pub struct NetceteraAuthenticationFailureResponse {
     pub error_details: NetceteraErrorDetails,
 }
 
+#[derive(Debug, Deserialize, Serialize)]
+#[serde(rename_all = "camelCase")]
+pub struct AuthenticationRequest {
+    #[serde(rename = "threeDSRequestorChallengeInd")]
+    pub three_ds_requestor_challenge_ind: Option<Vec<String>>,
+}
+
 #[derive(Debug, Deserialize, Serialize)]
 #[serde(rename_all = "camelCase")]
 pub struct AuthenticationResponse {