fix: add Expense doctype link to Expenses workspace and sidebar

Problem

The Expense doctype had no entry point in the Expenses workspace or its sidebar, making it hard to discover alongside Expense Claim and Expense Claim Type.

Root cause

The workspace's "Claims" card and the workspace sidebar were missing a link to Expense, and a stray duplicate Expense Claim Type link existed outside any card block in the workspace layout.

Fix

• Add an Expense link to the "Claims" card in the Expenses workspace.
• Move Expense Claim Type into its proper card position and remove the orphaned duplicate entry.
• Add an Expense link to the Expenses workspace sidebar.