[Feature Request]: Allow alternative sorting of Connections/Connection Groups

Nobody has claimed this yet.

### Feature Description

I would like to be able to sort connections and connection groups in an order other than alphabetical.

### Problem and Motivation

Personally I use the Groups for different environments and it would be helpful to be able to sort them by precedence. Currently it is ordered: "Dev", "Pre-Prod", "Prod", "UAT" which is a bit odd.
Similarly, but probably less important, ordering the connections within the group would also be helpful.

### Related Area

- [x] Connection dialog (SQL Server | Azure browse/Fabric browse)
- [ ] Query editor
- [ ] Query results panel
- [ ] Object Explorer
- [ ] GitHub Copilot integration
- [ ] Preview/Edit data
- [ ] Table Designer
- [ ] Schema Designer
- [ ] Schema Compare
- [ ] Local SQL Server Container provisioning
- [ ] SQL database in Fabric provisioning
- [ ] DACPAC/BACPAC export/import
- [ ] SQL Database projects
- [ ] Query Plan Visualizer
- [ ] Other (please describe below)

### If you selected "Other", please describe the area

_No response_

### Confirmation

- [x] I have searched existing feature requests and couldn't find a match
- [ ] I want to help implement this feature

Start in the connection dialog for SQL Server, Azure browse, and Fabric browse, and trace how connections and connection groups are currently ordered alphabetically. Define and implement a user-controlled ordering for groups and, if in scope, connections within groups; done means the selected order is reflected consistently in the dialog.

Written by the indexing model from the issue text.