docs(channels): Add screenshot for sesh

[josephschmitt]

📺 PR Description

Adds screenshot for sesh docs

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
• if this is a bug fix, I have added a test that reproduces the bug (if applicable)
• I have added a reasonable amount of documentation to the code where appropriate

[josephschmitt]

Adding integration docs to the Sesh project docs too: joshmedeski/sesh#309

[alexpasmantier]

Thanks!