fix: #3627380 Name the product "The Rightup" everywhere the recipe shows it

Issue: https://www.drupal.org/project/rightup/issues/3627380

The recipe showed the product name as "The Right Up", "The RightUp" and a bare "RightUp". This makes it "The Rightup" everywhere a viewer sees it, matching the theme name and the Drupal CMS installer listing. 37 files, 80 lines, all of it the product name. Machine names, file names and paths are untouched.

Direct replacements:

• The Right Up -> The Rightup (11)
• The RightUp -> The Rightup (16, all in the podcast transcripts)
• the RightUp / bare RightUp -> The Rightup
• Vartheme BS5 RightUp -> Vartheme BS5 Rightup, which is what the theme calls itself
• README badge label and its shields.io path

Places where "The Rightup" does not fit the sentence, so the sentence moved instead:

• The best of Right Up, delivered to you weekly. -> The best of The Rightup, ... (9 newsletter headings)
• Every Right Up show, in one place -> Every show from The Rightup, in one place
• the checked-out RightUp recipe -> the checked-out copy of The Rightup (.gitlab-ci.yml)
• is the square RightUp icon -> is The Rightup square icon (CHANGELOG)
• a fresh RightUp install -> a fresh install of The Rightup (live-feed.steps.js)
• On a RightUp site -> On The Rightup site (custom.steps.js)

custom.steps.js asserts the footer credit line, so its expected string moved with the copy.

All 335 YAML files parse, both step-definition files pass node --check, and a repo sweep for Right ?Up and The The returns nothing.

AI-Generated: Yes

Checkpoints:

• File an issue
• Addition/Change/Update/Fix
• Testing to ensure no regression
• Automated unit testing coverage
• Automated functional testing coverage
• UX/UI designer responsibilities
• Readability
• Accessibility
• Performance
• Security
• Developer Documentation
• User Guide Documentation
• Reviewed by human
• Code review by maintainers
• Full testing and approval
• Credit contributors
• Review with the product owner
• Release notes snippet
• Release