UI styling improvements: dashboard headers and navigation

- Restore blue PageHeader on Dashboard (/app-components)
- Update homepage (/) with subtle header design without blue bar
- Add uniform PageHeader styling to application edit page
- Fix Rapporten link on homepage to point to /reports overview
- Improve header descriptions spacing for better readability

.env.example

@@ -37,7 +37,6 @@ DATABASE_URL=postgresql://cmdb:cmdb-dev@localhost:5432/cmdb
 # Jira Assets Configuration
 # -----------------------------------------------------------------------------
 JIRA_HOST=https://jira.zuyderland.nl
-JIRA_SCHEMA_ID=your_schema_id
 
 # Jira Service Account Token (for read operations: sync, fetching data)
 # This token is used for all read operations from Jira Assets.