The module doc and the `.call` arm comment still said call result typing
"stays in Lowering" and "converges in A3.2". As of 7f3a7b3 calls are routed to
CallResolver (calls.zig); update both comments to name the current owner. The
`.call` arm still delegates through Lowering.inferExprType — that's the routing
path to the owner, not a claim that Lowering owns the typing.
Comment-only. Gate: zig build, zig build test, run_examples.sh -> 356/0.
64cd3da5f5