[FR] Allow navigating to any ticket by knowing its id only

[luolong]

I want to enable external issue tracker integration in Gitea projects to Taiga.

For this, I need to be able to provide a single URL template for a numeric ticket ID.
Because ticket links in Taiga contain ticket type element, there is no way to compose a universal issue reference link based on ticket number alone.

Moreover, I can't configure multiple links to Taiga issue tracker in Gitea, so I need a way to greate a link that can open any type of ticket referenced by its number in Taiga.

I propose to add a single endpoint that takes an id of any ticket as a path argument and redirects to a proper url based on a ticket type.

Something along the lines of:

GET /project/{project}/ticket/{id}

[mig5]

GET /project/{project}/ticket/{id}

I would go even further than that and suggest that every 'entity' (at least, a UserStory, Epic or Issue) should have a UUIDv4, and so it should be possible to find a story, epic or issue without even knowing the project slug.

Use case: I am importing from Pivotal Tracker which supports https://www.pivotaltracker.com/story/show/1234 or https://www.pivotaltracker.com/n/project/98765/story/show/1234 - both go to the same place.

As a result, we have a lot of comments/descriptions in content that happen to use the former style, depending on how the person pasted the link. This makes it hard to replace with a Taiga equivalent as part of our migration.