Update jsr:@fresh/init's generated dependencies

[lishaduck]

By default, the versions of Preact the Fresh v2 alpha and the scaffolded app different, so Deno creates two versions in node_modules, leading to TS errors at JSX expressions about how values of the type `ComponentChildren` is not assignable to type `ComponentChildren`. Also, on a fresh 😁 deno install (but not @fresh/init's install), it adds a lockfile. I think it's safe to add a lockfile by default now that the starter doesn't depend on esm.sh.