JD CLI updated: now creates filesystem folders

The JD CLI has been updated.

It's migrated from using environment variables to the new configuration file.

Now if you try to jd 11.11 to a folder, and that folder doesn't exist, and your JDex is readable by the CLI – i.e. Markdown files on disk, i.e. Obsidian - then it'll create the folder for you.

The MCP server has been updated to understand this tool and the configuration file. Just ask it to help me install the jd cli.

Here's a short video walkthrough.

If you installed the CLI before today

Pull:
```
git -C ~/.jd/cli pull
```

In your .zshrc or .bashrc, find these lines. You might only have the first.

source ~/.jd/cli/jd-nav/jd-nav.sh
source ~/.jd/cli/jd-prompt/jd-prompt.zsh

Replace them both with this line.
```
source ~/.jd/cli/jd.sh
```
Start a new shell.