Issue: [FEATURE]: Enable client_secret auth for payments - Get Intent [v2]

Required for SDK

Resolution: <think>
PR Context:
- Title: feat(router): Enable client_secret auth for payments_get_intent [v2]
- Merged: 2025-05-27T10:56:27Z
- Files changed: 1 files
- Commits: 1 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 -->
Added support for `client_secret` authentication in `Payments - Get Intent`

### Additional Changes

- [ ] This PR modifies the API contract
- [ ] This PR modifies the database schema
- [ ] This PR modifies application configuration/envi
</think>

To implement this, you'll need to modify:


**Detailed Implementation:**


**Commit 1:** feat(router): Enable client_secret auth for payments_get_intent [v2] (#8119)
Files to modify:


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