kanban: feature request: Organize issues by label

[Bl4ckT0ny]

• Gitea version (or commit ref): 13.3.2
• Git version: N/A
• Operating system: N/A
• Database (use [x]): N/A
• Can you reproduce the bug at https://try.gitea.io: N/A
• Log gist: N/A

Description

It would be great if we can organize issues by it's labels. Now developer should change issue's status label then go to project and move issue to the next board.

This feature is implemented in many collaboration systems such as gitlab, jira.

Proposal solution

• Add submenu Labels to board's "three dots" ... menu
• Open popup window
  • List of linked labels with ❌ button to unlink label
  • Drop-down list of available labels which is not linked to any boards of project
• Show issues on board filtered by it's labels.
• Unmatched issues are placed on "Backlog"/"Uncategorized" board
• There is an options how to resolve "Issue label hell" (multiple labels which matches multiple boards filter are linked to issue):
  • Show issue on multiple boards if it has multiple labels linked to different boards (ugly but easy)
  • Show issue on first (in order of boards) board which matches the issue label (preferred)
  • Show special board with label-conflicted issues (unusable)
  • Hide conflicted issues (non-intuitive)