[feature] Browser Steps: Reorder Steps

First of all: Thanks for sharing this as open source software and thanks for your work on this!

**Version and OS**
v0.40.0.4 on docker

**Is your feature request related to a problem? Please describe.**
When setting up necessary browser steps for a watch I sometimes forget a step or later notice that something is missing.

**Describe the solution you'd like**
I see two possible solutions to this:
1. Allow for reordering of browser steps. That way I could append the missing step and then move it into position
2. Allow a step to be inserted between two existing steps. Currently I can only append new steps at the end.

**Describe the use-case and give concrete real-world examples**
1. Make Browser Steps fill a form and click on next.
2. Notice you forgot to fill a necessary field that needs to be filled before clicking next.

Start by locating the browser-step editor and the code that executes saved steps, then trace how new steps are appended. Define whether reordering, insertion, or both are required, and verify that the edited order is persisted and used during watch execution.

Written by the indexing model from the issue text.