Frontend (Tanu-Key): Update layout of secret details page

Summary

This issue is for updating the secret details page to adhere to the latest designs.

Before	After

Implementation Notes

Some notable changes:

• Details page now has a two-column layout
• Details page now includes the secret's Status
• Environments is now its own field
• Addition of the Branches and Last Used field
• Removal of the Key field (it's redundant since it's already in the title)
• Created at field has been moved next to the Status label
• Date is now formatted to MM DD, YYYY

Links/References

📌 Figma.

Please refer to the main frontend epic for more information.