Marketplace sources of type strictKnownMarketplaces can now use pathPattern — a regex matched against .path of file and directory sources — to allow filesystem-based marketplaces alongside network source restrictions.
Evidence
Path pattern restrictions (search for "pathPattern", "Regex pattern matched against the .path field")
Strings lifted out of the shipped bundle, so the claim above can be checked against them.
One source agreesOne thing we can check says the same as this entry.
Anthropic's release notes agree
Added pathPattern to strictKnownMarketplaces for regex-matching file/directory marketplace sources alongside hostPattern restrictions