Function integration_base_for 

pub fn integration_base_for(data_dir: &Path, home_dir: &Path) -> PathBuf

Deploy shell integration scripts into <shell_root>/<type>/. Skips deployment if the version marker is already current. Errors are logged but not fatal — a missing script just means no integration. Root under which this instance’s shell-integration scripts are deployed.

Deliberately under the user’s home rather than the instance data dir: MSIX virtualises writes to %LocalAppData%, so scripts written there are invisible to the ConPTY-spawned children that must source them, while ~ is never virtualised (see shell/lifecycle.rs’s spawn path).

Keyed per instance, because the home dir is otherwise machine-global and every instance of every version writes these same files — on every shell spawn, not just at boot. Two concurrently-running versions therefore rewrite each other’s scripts indefinitely, and a shell can source an rcfile another instance is mid-replacement of. That is invariant I6 (instances of different (channel, version) never share a directory), and the key mirrors I5’s dir_hash treatment of named OS objects.

The data dir is the right key: it is <channel>/versions/<version>/data by construction, so it already distinguishes exactly the pairs I6 names.