api: fuzzy search task results cannot be navigated to by UI without an allocation

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Proposal

Add an allocation id to task fuzzy search results. How to actually choose an allocation if there is more than one is an open question.

Use-cases

The UI cannot navigate to a task without an allocation id:

That means the preliminary implementation in #10412 ignores the tasks collection returned by the fuzzy search endpoint because it can’t make use of them:

…
    "tasks": [
      {
        "ID": "fs-example",
        "Scope": [
          "default",
          "fs",
          "fs-example"
        ]
      }
    ],
…

Attempted Solutions

A possible workaround to find the necessary allocation id would be to run another query for every tasks returned, searching for allocations whose name matches tasks.[].Scope[2], the task group, but that would produce a lot of wasteful queries, so I stopped going down that path.