Unified URLs

[timpel-fcs]

Summary

Fixes #3022

• Rename generic URL fields to Supporting URL across initiate-proposal forms and the review step
• Add shared governance label constants and use them for vote reason and contract ID fields
• Add copyable Proposal Link field on proposal details via getProposalLink(contractId)
• Label vote reason text/URL in proposal details and cast-vote form as Vote Reason Summary / Vote Reason URL

Pull Request Checklist

Cluster Testing

• If a cluster test is required, comment /cluster_test on this PR to request it, and ping someone with access to the DA-internal system to approve it.
• If an upgrade test is required, comment /upgrade_test on this PR to request it, and ping someone with access to the DA-internal system to approve it.
• If a hard-migration test is required (from the latest release), comment /hdm_test on this PR to request it, and ping someone with access to the DA-internal system to approve it.
• If a logical synchronizer upgrade test is required (from canton-3.5), comment /lsu_test on this PR to request it, and ping someone with access to the DA-internal system to approve it.

PR Guidelines

• Include any change that might be observable by our partners or affect their deployment in the release notes.
• Specify fixed issues with Fixes #n, and mention issues worked on using #n
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Merge Guidelines

• Make the git commit message look sensible when squash-merging on GitHub (most likely: just copy your PR description).

[timpel-fcs]

@pawelperek-da

[pawelperek-da]

It needs a rebase to the new main @timpel-fcs

[timpel-fcs]

rebased @pawelperek-da

[pawelperek-da]

I think you missed [ci] in the commit message?

[timpel-fcs]

ah sorry, was not aware of this workflow rule, added 🙏

[isegall-da]

No need, PRs from forks by default use CI.

[isegall-da]

(unless we broke that, of course)

[pawelperek-da]

Probably I was just too impatient