feat(APP-3393): Update handling of proposal statuses

[cgero-eth]

Description

• Align proposal-status type to proposal-voting-status
• Make proposal-status strings customisable
• Export proposalStatusToTagVariant and proposalStatusToVotingStatus utiltities

Task: APP-3393

Type of change

• New feature (non-breaking change which adds functionality)

Checklist:

• I have selected the correct base branch.
• I have performed a self-review of my own code.
• I have commented my code, particularly in hard-to-understand areas.
• I have made corresponding changes to the documentation.
• My changes generate no new warnings.
• Any dependent changes have been merged and published in downstream modules.
• I ran all tests with success and extended them if necessary.
• I have updated the CHANGELOG.md file in the root folder of the package after the [UPCOMING] title and before
  the latest version.
• I have tested my code on the test network.