How to prevent Deno from automatic dependencies installation during `deno task`? Why does it happen?

Hey! I have a few problems with deps and deno taskdeno task.

One is, I have my own installinstall task that is running deno installdeno install with certain arguments (e.g. --allow-scripts--allow-scripts, --env-file--env-file etc). However, if I run deno task installdeno task install, it first installs the dependencies, before running my task. This is confusing and I don't know how to disable it.

Another is, Deno unexpectedly updates the lockfile when I don't ask it to. Here is a failing workflow: link. After installing packages with deno installdeno install (with frozen lockfile) in the workspace root, everything is fine. However, when running a task from a workspace member at tests/nodetests/node (the command is vitest runvitest run), Deno errors me that the lockfile is out of date - for some reason, it wants to add another entry for npm:vitestnpm:vitest.

So, first, I am curious why is it that Deno installs packages during deno taskdeno task in the first place, and second, why this behaviour is inconsistent in the workspace?