Add parentDir to API resources

[dotNomad]

Currently we have configurationRelPath and similar, which has a value of .posit/publish/python-staging.toml for example.

For Nested Project Deploying and the strings we will want to display we will need a new attribute in:

• Configurations
• Deployment Records
• ConfigurationDetails (returned by the Inspect API and passed to PUT /api/configurations/${NAME})

parentDir will contain the relative-to-the-workspace-root path of the directory containing the .posit directory.

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Part of the #1843 epic.