Clarify ComponentType guidance for solution components

[Sarthak-Agrawal]

Adds guidance before the AddSolutionComponentRequest sample explaining when to use ComponentType values, where common values come from, and when to prefer creating or updating the component in the target solution context with SolutionUniqueName.\n\nThis aligns the conceptual article with the more current guidance in the AddSolutionComponentRequest reference remarks.

[learn-build-service-prod]

Learn Build status updates of commit ccc656b:

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power-platform/alm/solution-api.md	✅Succeeded

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[phecke]

@Sarthak-Agrawal I have approved the PR. However, we always work in the private (-pr) repos - for example, power-platform-pr. After merging this PR, I will have to migrate the change to the private repo before the update can be published. Please keep this in mind the next time you work in our Learn repos.