Release 0.3.1

Added

• DisplayResolver integration — __main__.py integrates DisplayResolver from apcore-toolkit (optional) when --binding option is provided; gracefully skipped when not installed.
• init to BUILTIN_COMMANDS — init subcommand is now registered in the builtin commands set.
• APCORE_AUTH_API_KEY to man page — environment variable documented in generated roff man page.
• Grouped shell completion with _APCORE_GRP — bash/zsh/fish completion scripts now support two-level group/command completion via the _APCORE_GRP environment variable (shell.py).
• Path traversal validation for --dir in init command — rejects paths containing .. segments to prevent directory escape (init_cmd.py).

Fixed

• RegistryWriter API call — constructor now called without parameters; fixes TypeError introduced by upstream API change.

Changed

• apcore dependency bumped to >=0.14.0.

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