Wiki orchestration

Treat the installed product as code and the selected user vault as data. Never use the plugin/product root as a vault, even when the current directory happens to be the product checkout.

Resolve the portable core from this skill's installation and invoke it by absolute path:

CORE=/absolute/product/root/scripts/claude-obsidian.py
python3 "$CORE" --help

Resolve a vault in this order: explicit --vault, CLAUDE_OBSIDIAN_VAULT, the nearest .claude-obsidian.json, then an unambiguous initialized vault at or above the current directory. Fail closed when selection is missing or ambiguous.