Copy edit custom component documentation

[onyeepeace]

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Fixes 8362.

The PR enhances the OpenTelemetry Collector documentation by restructuring sentences for improved clarity, refining explanations of core concepts, and correcting grammatical errors.

These changes make the tutorial more accessible for implementing OpenTelemetry Collector components, reducing onboarding friction and potential misinterpretation of the API.

No functional code changes are included.

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: tiffany76 / name: Tiffany Hrabusa (4720cf6, 69c936f, d4ee160, 02b4708, 3415791, ac542a0, daf96d2)

[tiffany76]

Hi @onyeepeace! Thanks for putting this PR together. I've completed a partial review and made several suggestions to take the copy edits a little further. These pages needed some extra attention.

I will come back and review the last file very soon. It's quite large! In the meantime, feel free to address the comments I've already made. Thanks again!

[tiffany76]

This is great for a first pass of these very long pages! Thanks so much, @onyeepeace.

To keep things moving, I'm going to commit my suggestions so we can see where the PR stands.

[tiffany76]

@open-telemetry/collector-approvers - I know this is a long one. I tried to make sure the meaning wasn't changed anywhere. The Build a Receiver page will need further edits, but it was too much to do in this PR. If someone wants to take a look, that'd be great. Thanks!