feat: add custom source command names for multi-source channels

[nick4eva]

📺 PR Description

Add an optional command_name field to the [source] section of cable channel TOML definitions. When multiple source commands are defined, these names are displayed in the results panel header instead of the generic "Results" label, making it easier to identify which source is currently active.

Example usage:

[source]
command = ["ls", "ls -a", "ls -la"]
command_name = ["Default", "Hidden", "Detailed"]

Closes #1025

Checklist

• my commits and PR title follow the conventional commits format
• if this is a new feature, I have added tests to consolidate the feature and prevent regressions
• I have added a reasonable amount of documentation to the code where appropriate