Add a parameter to add a new folder automatically

### Feature summary

I want to be able to launch "github" with a parameter like "." "./github ." or "github /my/repo" and the repo would be added automatically in the session list

### What problem are you trying to solve?

I work with a huge number of repos, icking them one by one in the folder list is a waste of time. I'd like to be able to launch "github" command with a repository parameter (absolure or relative) so that the path would be added in the session list.

### Proposed solution

Add a parameter to the session.

### Workflow impact

add project easilly in the app

### Installation context

_No response_

### Additional context

_No response_

Start by locating the github launch command and the code that builds the session list; the issue names no source files or tests. Trace how command-line arguments are handled and define the behavior for relative and absolute repository paths, then add coverage showing that the supplied path appears in the session list.

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