Harden semantic boundaries and repair dialogue state

Replace nearest-neighbour personal routing with a frozen class-balanced linear head measured on historical, stratified, cross-validation, holdout, and fresh challenge gates (V-702). Close the four repair handoff holes, preserve nested clarification flows, and route Russian possession statements through structural grammar rather than lexical exceptions (V-573). Owner explicitly requested direct commits to master.

JOURNAL.md

@@ -186,3 +186,27 @@ showed that only the first initializes; later tests self-skip because the
 runtime is process-global. All V-702 figures were therefore rerun in separate
 processes. V-716 tracks fixing that harness gap rather than hiding it in this
 feature.
+
+### Forced dialogue and repair state
+
+V-573 closes all four repair seams exposed by the dialogue contract: a
+correction wins before a parked clarify answer; a repaired decision is checked
+for required slots before acting; a request completed through clarification is
+correctable; and declined or stale repairs do not prematurely spend the repair
+pointer. Same-intent corrections are handled explicitly without redoing the
+action, so their prose cannot route fresh and overwrite the retained pointer.
+
+The independent state audit found two deeper stack losses. A handled repair
+could leave an older question silently parked with its old TTL, and a repaired
+request needing clarification could overwrite—or, on completion, delete—the
+older flow. Repairs now suspend and audibly resume live questions, repaired
+questions push onto the bounded dialogue stack, and completion/cancellation
+pops only the active top before resuming the flow underneath.
+
+`MAVEN_DIALOGUE_NO_SKIP=1 go test -race ./cmd/mavend -run
+'^TestDialogueTraces$' -count=1` passes all 22 traces. The complete forced
+`cmd/mavend` race suite passes in 208.031s. The integrated race command over
+`cmd/mavend`, `internal/dialogue`, and all `internal/router` packages also
+passes (162.310s for mavend; every package green). Focused structural
+possession, repair-pointer, nested-stack, and repaired-clarify tests pass under
+the race detector.