Issue: Add support to call decision engine Dynamic Routing from hyperswitch after API key authentication

Resolution: <think>
PR Context:
- Title: feat(routing): Add API key auth for decision engine endpoints
- Merged: 2025-07-21T13:38:52Z
- Files changed: 8 files
- Commits: 10 commits

Implementation approach:
## Type of Change
<!-- Put an `x` in the boxes that apply -->

- [ ] Bugfix
- [x] New feature
- [ ] Enhancement
- [ ] Refactoring
- [ ] Dependency updates
- [ ] Documentation
- [ ] CI/CD

## Description
<!-- Describe your changes in detail -->
This PR adds API key auth to the decision engine endpoints for the decide gateway call and the update gateway score call.

### Additional Changes

- [x] This PR modifies the API contract
- [ ] This PR modifies the database schema
- [ ] T
</think>

To implement this, you'll need to modify:


**Detailed Implementation:**


**Commit 1:** feat(routing): Add API key auth for decision engine endpoints (#8640)
Co-authored-by: hyperswitch-bo
Files to modify:


**crates/api_models/src/events/routing.rs**
  Add:
    - function: private::get_api_event_type
    - function: private::get_api_event_type
    - function: private::get_api_event_type
    - function: private::get_api_event_type
    - impl: impl ApiEventMetric for crate::open_router::DecideGatewayResponse
    - impl: impl ApiEventMetric for crate::open_router::OpenRouterDecideGatewayRequest
    - impl: impl ApiEventMetric for crate::open_router::UpdateScorePayload
    - impl: impl ApiEventMetric for crate::open_router::UpdateScoreResponse

**crates/api_models/src/open_router.rs**
  Add:
    - struct: pub::DecideGatewayResponse
    - struct: pub::PriorityLogicOutput
    - struct: pub::PriorityLogicData

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

**crates/router/src/core/routing.rs**
  Add:
    - function: pub::decide_gateway_open_router
    - function: pub::update_gateway_score_open_router

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

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

**crates/router/src/routes/routing.rs**
  Add:
    - function: pub::call_decide_gateway_open_router
    - function: pub::call_update_gateway_score_open_router

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