Hide broken PDisk link on the VDisk page

[kkdras]

Problem

In Cloud UI, users with access via database_allowed_sids can open a VDisk page from database diagnostics, but the PDisk link from that page leads to /pDisk without the database query parameter.

Because of that, viewer/json/whoami is requested without database context, and the PDisk page shows No databases available.

Expected

Do not show clickable PDisk navigation on the VDisk page for database-scoped users. Keep the PDisk ID visible as plain/copyable text.

Acceptance criteria

• PDisk ID is still visible on the VDisk page.
• Database-scoped users are not shown a PDisk link/action that leads to No databases available.
• VDisk page layout and storage tabs keep working.