fix(bootstrap): keep the install alive on a host with only felis-api

restart_existing_control_plane ended in an and-list per deployment:

    [ "$had_api" = "1" ] && kube ... rollout restart deployment/felis-api
    [ "$had_operator" = "1" ] && kube ... rollout restart deployment/felis-operator

As the LAST command of a function, an and-list whose test is false returns 1,
and that becomes the function's exit status. The call site is bare, so under
`set -Eeuo pipefail` the installer dies there — after the bundle has been
applied and before the rollout wait, leaving a half-finished upgrade and no
message naming the cause.

It fires on any host carrying one control-plane deployment but not the other:
felis-api present without felis-operator restarts the api, then exits 1 on the
second test. Both present, or neither, happened to work, which is why it
survived.

Rewritten as explicit `if` statements, which return 0 when the test is false.
Verified out of tree against all four had_api/had_operator combinations.