v0.4.0

Installed-version introspection + version reconciliation (issue #1). Handles targets that have BOTH a web-latest and a locally-installed version.

• MCP introspect gains kind:"r-pkg" — a READ-ONLY probe of a locally installed R package's version via Rscript (name-guarded, passed as an arg not -e, watchdog-timed). Returns installed_version + the resolved_env (.libPaths() entry) it came from, or an honest "not installed in the current context" — never a fabricated global version. Never installs.
• docs-router skill gains per-question target-type classification (has-local vs web-only) and a version-reconciliation state machine: for a has-local query, introspect the installed version + fetch web-latest, then always defer to local (web only gates the upgrade decision); a chosen upgrade is run by the skill after explicit confirmation, and the MCP stays read-only. web-only targets (e.g. Claude Code features/config, SaaS) skip reconciliation entirely.