#3669 batch: two functions over the complexity ratchet (run_shapes_gate NEW 13/28, dispatch_runtime_commands GROWN 41->43) — extract helpers, no behaviour change #3681

Batch #3669's guard-tree was RED on check_complexity_ratchet.sh vs main 79a3af79d:

RED  NEW    crates/aprender-contracts/src/lint/shapes_gate.rs::run_shapes_gate  cyclomatic 13 cognitive 28
RED  GROWN  crates/apr-cli/src/dispatch.rs::dispatch_runtime_commands  cognitive 41 -> 43, cyclomatic 15 -> 16

The first comes from #3600's edits and the second from #3604 (--revalidate env seam) and #3638/#3602 (the accelerator classifier). None of the constituents can be dropped from the 0.69 platform.

Acceptance

1. run_shapes_gate is under the threshold (cyclomatic < 30, cognitive ≤ 25) and dispatch_runtime_commands is back to main's 15/41. bash scripts/check_complexity_ratchet.sh reports none new, none grown.
2. No behaviour change. Each extraction moves code verbatim into a helper: same order, same outcomes. cargo test -p aprender-contracts --lib has the same pass count as before (1684), and cargo test -p apr-cli --lib dispatch/registry pass. Clippy -D warnings is clean on both crates.
3. Nothing else in the diff: only shapes_gate.rs and dispatch.rs, plus this row's roadmap fragment.

Refs #3669 #3600 #3604 #3602