Covers #2546: a logged-in user navigating to a public link share URL
used to bounce infinitely between /share/:hash/auth and the project
view, stranding the user on an empty NoAuthWrapper shell. Two distinct
issues in checkAuth() produced the same symptom:
1. The 1-minute debounce skipped re-parsing the new link share JWT
when the user was already authenticated.
2. The "same user, skip setUser" fast path compared only `id`, so a
logged-in user whose id collided with the link share's id kept
the USER `info.value.type` and `authLinkShare` never flipped.
The test pins both the logged-in user and the link share to the same
numeric id so it exercises the collision path, which catches both
regressions at once.
a574d623b1