Add B.Jumblr by sjaehn

[kmturley]

Summary

• Adds B.Jumblr, a pattern-controlled audio stream/sample re-sequencer LV2 plugin.
• GPL-3.0. type: generator. Dropped a redundant .zip duplicate of the .tar.xz (verified identical content, same 24 files).

Test plan

• npx tsx src/validate.ts src/plugins/sjaehn/bjumblr/1.6.8/index.yaml passes

[github-actions]

VirusTotal Report:

• test/downloads/sjaehn/bjumblr/1.6.8/0-BJumblr-1.6.8-linux-amd64.lv2.tar.xz

[github-actions]

Destination urls:
Registry: https://open-audio-stack.github.io/open-audio-stack-registry/plugins/sjaehn/bjumblr
Site: https://studiorack.github.io/studiorack-site/plugins/sjaehn/bjumblr

[github-actions]

Plugin author notification:

@sjaehn — your plugin has been submitted to the Open Audio Stack registry. Please review this PR and let us know if the metadata (name, description, tags, files) is correct. To see a full list of all currently added plugins, click here.