Issue:
Todo redis interface

## Type of Change
<!-- Put an `x` in the boxes that apply -->
- [x] Enhancement

## Description
This PR is a part of greater refactoring which aims on removing `// TODO: ...` & `// FIXME: ..` from the entire codebase.
The objective of this PR is to fix `xgroup_create` by adding a guard or some specific `RedisEntryId` while also adding unit tests for the same. It also adds crate documentation for the `redis_interface` crate
<!-- Describe your changes in detail -->


### Additional Changes

- [ ] This PR modifies the database schema
- [ ] This PR modifies application configuration/environment variables

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Provide links to the files with corresponding changes.

Following are the paths where you can find config files:
1. `config`
2. `crates/router/src/configs`
3. `loadtest/config`
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## Motivation and Context
The codebase wide initiative in fixing existing problems, `TODO:`s and `FIXME:`s while also adding documentations.
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## How did you test it?
unit-tests included
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## Checklist
<!-- Put an `x` in the boxes that apply -->

- [x] I formatted the code `cargo +nightly fmt`
- [x] I addressed lints thrown by `cargo clippy`
- [x] I reviewed submitted code
- [x] I added unit tests for my changes where possible

Resolution:
<think>
PR Context:
- Title: fix: todos and fixmes resolution for api_models
- Merged: 2022-12-14T12:19:48Z
- Files changed: 17 files
- Commits: 6 commits

Implementation approach:
## Type of Change
<!-- Put an `x` in the boxes that apply -->
- [x] Enhancement

## Description
This PR targets on removing `// TODO: ..` & `// FIXME: ..` specifically from the `api_models`

This PR is part of the chain of micro PR's focused on removing todo
1. #136 
2. #139 
<!-- Describe your changes in detail -->


### Additional Changes

- [x] This PR modifies the database schema
- [ ] This PR modifies application configuration/environment variables

<!-- 
Provide links to
</think>

To implement this, you'll need to modify:


**Detailed Implementation:**


**Commit 1:** fix: todos and fixmes resolution for api_models (#144)
Files to modify:


**crates/api_models/src/admin.rs**
  Modify existing code

**crates/api_models/src/payment_methods.rs**
  Add:
    - enum: pub::PaymentExperience

**crates/api_models/src/payments.rs**
  Modify existing code

**crates/api_models/src/refunds.rs**
  Add:
    - enum: pub::RefundType

**crates/masking/src/abs.rs**
  Modify existing code

**crates/router/src/core/payment_methods/cards.rs**
  Modify existing code

**crates/router/src/core/payment_methods/transformers.rs**
  Modify existing code

**crates/router/src/core/payments/operations/payment_response.rs**
  Modify existing code

**crates/router/src/core/payments/transformers.rs**
  Modify existing code

**crates/router/src/core/refunds.rs**
  Modify existing code

**crates/router/src/db/payment_attempt.rs**
  Modify existing code

**crates/router/src/types/transformers.rs**
  Add:
    - function: private::from
    - impl: impl From<F<api_models::refunds::RefundType>> for F<storage_enums::RefundType>

**crates/storage_models/src/payment_attempt.rs**
  Modify existing code

**crates/storage_models/src/schema.rs**
  Modify existing code