test: add dedicated playwright regression workflow and sync tests with ENT (#11677)

## Summary
- Added `playwright_regression.yml` with one-shard-per-spec parallelism
(11 regression specs)
- Removed `RegressionSet` shard from main `playwright.yml` (tests now
run via dedicated regression workflow)
- Added `Cache test failures to TestDino` step to regression workflow
(matching main playwright.yml)
- Uses `ubicloud-standard-8` runners for all regression jobs

## Schedule
- Auto-triggers every 4 hours starting from 9 AM IST (3:30, 7:30, 11:30,
15:30, 19:30, 23:30 UTC)
- Manual trigger via `workflow_dispatch`

## Test Plan
- [ ] Confirm `playwright_regression.yml` appears in Actions tab
- [ ] Trigger a manual run to verify all 11 regression specs run in
parallel
- [ ] Verify `playwright.yml` no longer includes RegressionSet shard

---------

Co-authored-by: Claude Opus 4.7 <noreply@anthropic.com>

tests/ui-testing/playwright-tests/Logs/logs-autocomplete-suggestions.spec.js

@@ -987,11 +987,13 @@ test.describe("Autocomplete Value Suggestions - Quoting Behavior", () => {
         await pm.logsPage.selectStream(streamName);
         await runQueryAndWaitForResults(page, pm);
 
-        // Find a numeric field (like 'code' which has HTTP status codes)
-        const codeFieldBtn = page.locator(pm.logsPage.fieldExpandButton('code'));
-        const codeFieldExists = await codeFieldBtn.count() > 0;
-        expect(codeFieldExists, 'Expected "code" field to exist for numeric quoting test').toBe(true);
+        // Search for the field in the field list search box first
+        await pm.logsPage.searchFieldByName('code');
+        await page.waitForTimeout(1000);
 
+        // Find the field expand button for 'code'
+        const codeFieldBtn = page.locator(pm.logsPage.fieldExpandButton('code'));
+        await codeFieldBtn.waitFor({ state: 'visible', timeout: 5000 });
         await codeFieldBtn.click();
         await page.waitForTimeout(2000);