Improve robustness of podman system reset

Firstly, reset is now managed by the runtime itself as a part of
initialization. This ensures that it can be used even with
runtimes that would otherwise fail to be created - most notably,
when the user has changed a core path
(runroot/root/tmpdir/staticdir).

Secondly, we now attempt a best-effort removal even if the store
completely fails to be configured.

Third, we now hold the alive lock for the entire reset operation.
This ensures that no other Podman process can start while we are
running a system reset, and removes any possibility of a race
where a user tries to create containers or pull images while we
are trying to perform a reset.

[NO NEW TESTS NEEDED] we do not test reset last I checked.

Fixes #9075

Signed-off-by: Matthew Heon <mheon@redhat.com>

libpod/options.go

@@ -435,6 +435,21 @@ func WithDefaultInfraCommand(cmd string) RuntimeOption {
 	}
 }
 
+// WithReset instructs libpod to reset all storage to factory defaults.
+// All containers, pods, volumes, images, and networks will be removed.
+// All directories created by Libpod will be removed.
+func WithReset() RuntimeOption {
+	return func(rt *Runtime) error {
+		if rt.valid {
+			return define.ErrRuntimeFinalized
+		}
+
+		rt.doReset = true
+
+		return nil
+	}
+}
+
 // WithRenumber instructs libpod to perform a lock renumbering while
 // initializing. This will handle migrations from early versions of libpod with
 // file locks to newer versions with SHM locking, as well as changes in the