Suggestions for improvements to Field Cert page

Why is this change being made?

Per the Field Cert core team's request, I took a look at the Field Cert Handbook page and made some recommended changes. A summary of the changes includes:

1. Changed the flow of information to present in a more logical/grouped way:
   • Overview, including:
     • Goal - Reworked these from questions to statements
     • Purpose - Reworked these from questions to statements
     • MTM definition - I pulled this up because we mentioned MTM in the intro but then didn't define it until farther down the page. Might be a little too disassociated in that format for people who are unfamiliar with MTM.
     • Audience - Felt like it made more sense nested under the overview vs. standalone
2. Grouped Delivery and nested Assessments under it, as it all felt like part of how the course would be delivered.
   1. I'd imagine eventually this section would also include guidance on how to access the LXP, how the badges work, etc.
3. Finished with Roadmap, as it felt like a more natural place to leave off – "where we're headed"

A few additional pieces of feedback (not format-related):

1. In the Certification Levels section, it's likely worth adding some language in about the fact that we will be in "Level 1" for the foreseeable future. I know we link to a roadmap farther down but it didn't seem super apparent either. Essentially, just an opportunity for us to drive home the full extent of these levels and set an expectation for when team members will be expected to participate in additional levels.
2. In regards to the leveling table, I still struggle with this one, as it feels like the Level Name should map back to whatever distinction we will give the team member once they complete that level.
   1. I don't have the answer to this at all, just calling it out!
3. The leveling table has a column for "color highlight" but it's unclear as to what that is referring to.

Author Checklist

• Provided a concise title for the MR
• Added a description to this MR explaining the reasons for the proposed change, per [say-why-not-just-what][transparency]
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