A module boundary that had quietly merged

Two modules with a layer rule permitting each to depend on the other, which is not a boundary.

ruleset:
  Catalogue: [Shared, Pricing]
  Pricing:   [Shared, Catalogue]     # ← bidirectional

# added in 2023 "temporarily" to unblock a release, and
# never revisited. 88 edges in each direction.

A rule that permits a cycle is a rule that documents the absence of a boundary, and it passed CI every day for two years because the tool was doing exactly what it was told. Merging them into one module was a two-line configuration change and an honest description of what the code already was — the alternative, untangling 176 edges, was costed at three weeks for no benefit anybody could name.