This commit restructures the paperless-ai Helm chart by moving all files
from the nested directory (charts/paperless-ai/paperless-ai/) to the
standard Helm chart directory structure (charts/paperless-ai/). The change
eliminates the redundant directory nesting that was causing issues with
Helm chart packaging and installation. No functional changes were made to
any files - this is purely a directory structure reorganization to follow
Helm best practices and improve chart maintainability.