feat(deploy-docs): add branch- prefix for non-default branches

[xmfcx]

Description

• 🚨 Merge first: feat(deploy-docs): name version through tag #362

I want to clean up this mess:

For this, the first step is to organize them.

I want to sort them like:

• main
• 1.4
• 1.3
• ... other versions
• pr-333
• pr-222
• ... other prs
• branch-chore-x
• branch-feat-y
• ... alphabetically workflow dispatches

And for this, I first want to prefix the versions that are triggered by the workflow dispatches with branch-.

Also for the cleanup mechanism, we have https://github.com/autowarefoundation/autoware-github-actions/blob/main/delete-closed-pr-docs/action.yaml but it doesn't clean up dangling branches that were used for workflow-dispatch but later removed. That will be in another PR.

Tests performed

• https://github.com/xmfcx/autoware-documentation/actions/runs/19802565719/job/56731957709#step:3:280 (default) main branch is deployed as expected. ✅
• https://github.com/xmfcx/autoware-documentation/actions/runs/19802642166/job/56732136120#step:3:280 on workflow dispatch, deploys to branch-feat-test (branch name was feat/test ✅

The pull requests are already prefixed with pr- and no change.

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[xmfcx]

@mitsudome-r could you review this too?

[xmfcx]

• https://github.com/autowarefoundation/autoware-github-actions/releases/tag/v1.60.0 released.