bug: stale instance entries accumulate in config when container is recreated

[Syedowais312]

Describe the bug

Description

When a container is removed externally (e.g. docker stop && docker rm) and
microcks start recreates it, the old instance entry is never removed from config.
A new entry is appended instead, causing duplicate instance records to accumulate.

Expected behavior

No response

Actual behavior

No response

How to Reproduce?

Steps to Reproduce

1. ./microcks start
2. docker stop microcks && docker rm microcks
3. ./microcks start
4. cat ~/.config/microcks/config two instance entries with same name but different container IDs

Screenshots

Root Cause

RemoveInstance matched by Name instead of ContainerID. Since the recreated
container has a new ID, UpsertInstance never finds a match and always appends.

Microcks version or git rev

No response

Install method (docker-compose, helm chart, operator, docker-desktop extension,...)

No response

Additional information

No response