AO3-7180: Mark "Name" field as required when creating a new pseud

[name-hansel]

• Also rename the page title and create button

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Issue

https://otwarchive.atlassian.net/browse/AO3-7180

Purpose

• Mark "Name" field as required when creating a new pseud by adding "(required)" right to the label
• Add required class
• Change page title to use titlecase
• Rename "Create" button to "Create Pseud"

Not sure if this is sufficient to mark the "Name" field as required - please let me know if anything else has to be included!

Credit

Snehal Mane

[sarken]

This is exactly right -- thank you!

If you could address the code style comments from reviewdog, this will be ready to merge.