Issue:
update refunds filters and list

Include filter for amount and merchant connector id in refunds list.

Resolution:
<think>
PR Context:
- Title: feat(refunds): update refunds filters
- Merged: 2024-05-13T13:31:58Z
- Files changed: 14 files
- Commits: 12 commits

Implementation approach:
## Type of Change
<!-- Put an `x` in the boxes that apply -->

- [ ] Bugfix
- [x] New feature
- [x] Enhancement
- [ ] Refactoring
- [ ] Dependency updates
- [ ] Documentation
- [ ] CI/CD

## Description
The PR:
- Adds support for new `filter_v2` api to get list of available filters for refunds quickly: connector with their corresponding label with merchant_connector_ids, currency and refund status. This api is quicker than previous one and gives static and dynamic filter. In this li
</think>

To implement this, you'll need to modify:


**Detailed Implementation:**


**Commit 1:** feat(refunds): update refunds filters (#4409)
Co-authored-by: hyperswitch-bot[bot] <148525504+hypers
Files to modify:


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

**crates/api_models/src/events/refund.rs**
  Add:
    - function: private::get_api_event_type
    - impl: impl ApiEventMetric for RefundListFilters

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

**crates/api_models/src/refunds.rs**
  Add:
    - struct: pub::RefundListFilters

**crates/common_enums/src/enums.rs**
  Modify existing code

**crates/openapi/src/openapi.rs**
  Modify existing code

**crates/router/src/core/refunds.rs**
  Add:
    - function: pub::get_filters_for_refunds

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

**crates/router/src/routes/app.rs**
  Modify existing code

**crates/router/src/routes/lock_utils.rs**
  Modify existing code

**crates/router/src/routes/refunds.rs**
  Add:
    - function: pub::get_refunds_filters

**crates/router/src/types/storage/refund.rs**
  Modify existing code

**crates/router_env/src/logger/types.rs**
  Modify existing code