fix(charts): Force refresh uses async mode when GAQ is enabled

[msyavuz]

SUMMARY

Fixed an issue where manual chart refreshes were loading in sync mode instead of async mode when Global Async Queries (GAQ) is enabled.

BEFORE/AFTER SCREENSHOTS OR ANIMATED GIF

TESTING INSTRUCTIONS

1. Enable Global Async Queries (GAQ) in your Superset configuration
2. Load a dashboard with charts (ensure cache is empty initially)
3. Open Network tab in browser DevTools
4. Note initial chart loads return HTTP 202 (async mode)
5. Click the three ellipses menu on a chart and select "Force refresh"
6. Verify the refresh request returns HTTP 202 (async mode)
7. Test dashboard-level refresh button as well

ADDITIONAL INFORMATION

• Has associated issue:
• Required feature flags:
• Changes UI
• Includes DB Migration (follow approval process in SIP-59)
  • Migration is atomic, supports rollback & is backwards-compatible
  • Confirm DB migration upgrade and downgrade tested
  • Runtime estimates and downtime expectations provided
• Introduces new feature or API
• Removes existing feature or API