refactor(aura-runner, aura-cli): retire the family builders and the CLI topology_hash duplicate

Slice 7 of the #319 retirement. aura-runner's blueprint_sweep_family /
blueprint_walkforward_family / blueprint_mc_family lost their only
production callers with the quintet and are gone (family.rs 889 -> 199
lines) together with their zero-caller helpers; reproduce's live inputs
(DataSource, showcase/walkforward sources) stay. Coverage was ported
first: member-computation identity + family-shared topology_hash now pin
through a campaign-document twin in tests/exec.rs, reproduce's multi-member
and MC-seed-label branches re-mint their fixtures directly. The CLI-side
topology_hash helper goes with them — its keep-rationale was disproven
(the record line's hash is computed in the runner's member machinery;
minuted on the issue) — and c28_layering's file list drops the stale
verb_sugar entry. The synthetic per-seed MC family remains an intentional
retirement casualty, recorded in the test dispositions.

refs #319

crates/aura-cli/src/graph_construct.rs

@@ -663,8 +663,11 @@ pub fn introspect_cmd(cmd: crate::GraphIntrospectCmd, env: &aura_runner::project
         // The content id (#158) is the SHA256 of the same `blueprint_to_json`
         // bytes `graph build` emits; the identity id (#171) the SHA256 of the
         // debug-name-blind `blueprint_identity_json` form — both via the one
-        // shared `crate::content_id` primitive `topology_hash` also uses, so all
-        // surfaces agree by construction.
+        // shared `crate::content_id` primitive, the same hash the run
+        // manifest's `topology_hash` uses (computed inline in
+        // `aura_runner::member`'s `run_signal_r`/`run_blueprint_member` — #319
+        // Task 9 retired the CLI-side `topology_hash` wrapper this comment
+        // used to name), so all surfaces agree by construction.
         let composite = match cmd.content_id.as_ref() {
             Some(Some(file)) => {
                 let text = match std::fs::read_to_string(file) {