fix: remove stale instance entry on recreate and guard stop against missing containers

[Syedowais312]

Problem

When a container is removed externally (e.g. docker system prune) and
microcks start recreates it, the old instance entry was never removed from
config causing duplicate instance records to accumulate on every recreate.

Two root causes:

1. RemoveInstance matched by Name (not unique) instead of ContainerID (unique)
2. The autoRemove path in stop.go was passing instance.Name to RemoveInstance,
   silently failing to remove the correct entry
3. start.go was clearing instance.ContainerID = "" instead of calling
   RemoveInstance to actually remove the stale record from config

Changes

• cmd/start.go: call localConfig.RemoveInstance(instance.ContainerID) to
  remove the stale record before recreating, instead of just clearing the local variable
• cmd/stop.go: pass instance.ContainerID to RemoveInstance in the autoRemove path
• pkg/config/localconfig.go: RemoveInstance now matches by ContainerID instead of Name

Testing

Ran docker rm <container> while config shows status: Running, then
microcks start --name <instance> config shows a single clean entry with
the new container ID, no duplicates.

Realted: #456

Fix: #483

[Vaishnav88sk]

Matching by ContainerID instead of Name is the correct approach. Could you add a test case for the duplicate-entry scenario?

[Syedowais312]

Matching by ContainerID instead of Name is the correct approach. Could you add a test case for the duplicate-entry scenario?

i have added appropriate test cases in pkg/config/localconfig_test.go

[Vaishnav88sk]

Thanks for adding tests after the earlier review feedback.

One thing I want to call out: the PR title mentions “guard stop against missing containers”, but I don’t see an actual missing-container guard added in stop.go in this diff. So:

• add the missing guard behavior as well.

[Syedowais312]

Thanks for adding tests after the earlier review feedback.

One thing I want to call out: the PR title mentions “guard stop against missing containers”, but I don’t see an actual missing-container guard added in stop.go in this diff. So:

sorry i missed it earlier.
i have added a checks to verify whether the container still exists before trying to stop it.