Feature/dynamic prompt management + some bug fixing

[giusedroid]

Issues #14, #15, #16, #24

Description of changes:

• [#14, #15] Users can now override the system default prompt on demand and dynamically via script.
• [#16] fixed issue with asking questions when lancedb table for this identity does not exist
• [#24] fixed issue with access denied when navigating directly to a sub-path, such as /Documents or /Settings

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