[FEATURE] Add check in viash ns ... to check namespace/component_name uniqueness

[Grifs]

Feature summary

Verify that all picked up components have an unique namespace & component_name combination.

Feature description

It is currently possible to define 2 or more files with the same namespace & component names.
src/ns1/comp.vsh.yml and src/ns2/comp.vsh.yml
both containing:

functionality:
  name: comp
  namespace: ns

Why is this feature beneficial?

Prevents collisions down the road.

Alternatives considered

No response

Possible solution

No response

Confirmation

• I have searched the existing issues to make sure this is not a duplicate request.
• I have provided clear and concise information about the feature.

[Grifs]

Implemented in Viash 0.8.6