CCM-14430 letter interim process

[emmagifford]

Description

Main changes are as follows.

In /upload-a-letter:

• changed the numbered steps to align with the temporary letters flow process
• added inset text to highlight the new process
• updated all the blank Word templates to include the new {d.} syntax/Markdown for adding personalisation fields

In /personalisation:

• added new content on adding personalisation fields to letter templates using the different {d. } Markdown - this includes an example

I've incorporated feedback from Stace's initial 2i, which was incredibly helpful!

Context

CCM-14430 explains the context of why this is needed. If I'm not around, if you could please add a comment on the ticket once the content is live, that would be much appreciated! Then Lee P is aware.

Type of changes

• Refactoring (non-breaking change)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would change existing functionality)
• Bug fix (non-breaking change which fixes an issue)

Checklist

• I am familiar with the contributing guidelines
• I have followed the code style of the project
• I have added tests to cover my changes
• I have updated the documentation accordingly
• This PR is a result of pair or mob programming

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Sensitive Information Declaration

To ensure the utmost confidentiality and protect your and others privacy, we kindly ask you to NOT including PII (Personal Identifiable Information) / PID (Personal Identifiable Data) or any other sensitive data in this PR (Pull Request) and the codebase changes. We will remove any PR that do contain any sensitive information. We really appreciate your cooperation in this matter.

• I confirm that neither PII/PID nor sensitive data are included in this PR and the codebase changes.