Backport of [UI] - Glimmerize b64-toggle component into release/1.20.x

[hc-github-team-secure-vault-core]

Backport

This PR is auto-generated from #31423 to be assessed for backporting due to the inclusion of the label backport/1.20.x.

🚨

Warning automatic cherry-pick of commits failed. If the first commit failed,
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will see the cherry-picked commits up to, not including, the commit where
the merge conflict occurred.

The person who merged in the original PR is:
@meirish
This person should resolve the merge-conflict(s) by either:

• Manually completing the cherry picks into this branch
• Creating a new branch and manually cherry-picking all commits being backported

merge conflict error: POST https://api.github.com/repos/hashicorp/vault/merges: 409 Merge conflict []

The below text is copied from the body of the original PR.

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Description

This is the start of refactoring out all usage of @ember/component. I took the refactoring work as a chance to use Copilot more. It does a pretty good job on converting things (especially with the custom instructions I've included, more about them in a minute). The biggest issue was re-working this component so that the data flow was uni-directional which also necessitated some updates to the usage sites.

https://hashicorp.atlassian.net/browse/VAULT-38592

Copilot usage

I built off of the work @beagins did for the hackweek. In addition to that I added an instruction which was copy and pasting the upgrading to Octane docs from Ember's guide site here: https://github.com/ember-learn/guides-source/tree/master/guides/v5.9.0/upgrading/current-edition

This meant Copilot could get really far. I opened the b64-toggle.js component and prompted Copilot with "Convert this file to a glimmer component".

TODO only if you're a HashiCorp employee

• Backport Labels: If this fix needs to be backported, use the appropriate backport/ label that matches the desired release branch. Note that in the CE repo, the latest release branch will look like backport/x.x.x, but older release branches will be backport/ent/x.x.x+ent.
  • LTS: If this fixes a critical security vulnerability or severity 1 bug, it will also need to be backported to the current LTS versions of Vault. To ensure this, use all available enterprise labels.
• ENT Breakage: If this PR either 1) removes a public function OR 2) changes the signature
  of a public function, even if that change is in a CE file, double check that
  applying the patch for this PR to the ENT repo and running tests doesn't
  break any tests. Sometimes ENT only tests rely on public functions in CE
  files.
• Jira: If this change has an associated Jira, it's referenced either
  in the PR description, commit message, or branch name.
• RFC: If this change has an associated RFC, please link it in the description.
• ENT PR: If this change has an associated ENT PR, please link it in the
  description. Also, make sure the changelog is in this PR, not in your ENT PR.

PCI review checklist

• I have documented a clear reason for, and description of, the change I am making.
• If applicable, I've documented a plan to revert these changes if they require more than reverting the pull request.
• If applicable, I've documented the impact of any changes to security controls.

Examples of changes to security controls include using new access control methods, adding or removing logging pipelines, etc.

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Overview of commits

• 32e806f

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Project	Deployment	Preview	Comments	Updated (UTC)
vault-ui	🛑 Canceled			Aug 12, 2025 4:25pm

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CI Results:
All Go tests succeeded! ✅