Fix: pdf chunking / table rotation (#12981)

### What problem does this PR solve?

Fix: PDF chunking issue for single-page documents
Refactor: Change the default refresh frequency to 5
Fix: Add a 0-degree threshold; require other rotation angles to exceed
it by at least 0.2
Fix: Put connector name tips to correct place
Fix: incorrect example response in delete datasets.

### Type of change

- [x] Bug Fix (non-breaking change which fixes an issue)
- [x] Refactoring

web/src/pages/user-setting/data-source/constant/confluence-constant.tsx

@@ -7,7 +7,6 @@ export const confluenceConstant = (t: TFunction) => [
     name: 'config.credentials.confluence_username',
     type: FormFieldType.Text,
     required: true,
-    tooltip: t('setting.connectorNameTip'),
   },
   {
     label: 'Confluence Access Token',

web/src/pages/user-setting/data-source/constant/index.tsx

@@ -200,6 +200,7 @@ export const DataSourceFormBaseFields = [
     name: 'name',
     type: FormFieldType.Text,
     required: true,
+    tooltip: t('setting.connectorNameTip'),
   },
   {
     label: 'Source',