docs: remove outdated manual sync instance schema section

[d-bytebase]

Summary

• Removed the "Sync instance schema" section from the add-an-instance documentation
• This section described a manual sync process that is no longer needed
• Instance schema is now automatically synchronized upon instance creation

Why this change?

The documentation was outdated and could confuse users. When an instance is added to Bytebase, the schema synchronization happens automatically - users no longer need to manually click "Sync Now" as a separate step after adding an instance.

Keeping this section in the documentation would lead users to look for a "Sync Now" button that may not be prominently displayed or necessary for the initial setup, potentially causing confusion during onboarding.

Test plan

• Verified the MDX file renders correctly without the removed section
• Confirm that new instances automatically sync their schema upon creation
• Check that the documentation flow remains clear without this section

🤖 Generated with Claude Code

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Project	Deployment	Preview	Comments	Updated (UTC)
bytebase-com	Ready	Preview	Comment	Aug 21, 2025 7:35am

[Copilot]

Pull Request Overview

This PR removes an outdated section from the instance setup documentation that described a manual schema synchronization process that is no longer required.

• Removes the "Sync instance schema" section that instructed users to manually click "Sync Now"
• Eliminates outdated information about manual schema synchronization after instance creation
• Streamlines the documentation to reflect current automatic schema sync behavior

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[github-actions]

📝 Broken Links Check Report

Note: Entries under /api-reference/ are likely false positives and can be ignored.

The following is the output from the broken links check:

found 16 broken links in 9 files

integrations/api/audit-log.mdx
 ⎿  /api-reference/auditlogservice/post-v1auditlogs:search

integrations/api/authentication.mdx
 ⎿  /api-reference/authservice/post-v1authlogin

integrations/api/data-classification.mdx
 ⎿  /api-reference/settingservice/patch-v1settings
 ⎿  /api-reference/databaseservice/patch-v1instances-databases

integrations/api/issue.mdx
 ⎿  /api-reference/issueservice/post-v1projects-issues

integrations/api/permission.mdx
 ⎿  /api-reference/workspaceservice/get-v1workspaces-:getIamPolicy
 ⎿  /api-reference/projectservice/get-v1projects-:getIamPolicy
 ⎿  /api-reference/roleservice/get-v1roles
 ⎿  /api-reference/userservice/get-v1users
 ⎿  /api-reference/groupservice/get-v1groups

integrations/api/plan.mdx
 ⎿  /api-reference/planservice/post-v1projects-plans
 ⎿  /api-reference/sheetservice/post-v1projects-sheets

integrations/api/release.mdx
 ⎿  /api-reference/releaseservice/post-v1projects-releases

integrations/api/rollout.mdx
 ⎿  /api-reference/rolloutservice/post-v1projects-rollouts

integrations/api/sql-review.mdx
 ⎿  /api-reference/releaseservice/post-v1projects-releases:check
 ⎿  /api-reference/sqlservice/post-v1sqlcheck