feat(suppress): group-suppress warnings + ls + journey + docs (M1.5)

- dangling_suppress_warnings takes an ApplyOwner and walks the group's own
  chain (GROUP_CHAIN_LEVELS_CTE) for a group node; runs for both owners.
- GET /groups/{id}/suppressions + `pic suppress ls --group` (client + cmd +
  main.rs; --app/--group mutually exclusive).
- suppress journey: a child group declines a parent template for its subtree;
  suppress ls --group shows the marker. Docs §4.5 + CLAUDE.md move group-level
  suppression from Deferred to implemented.

Completes M1. (An unrelated pre-existing email_inbound dispatch-timing flake
passes in isolation.)

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

crates/manager-core/src/apply_api.rs

@@ -45,6 +45,7 @@ pub fn apply_router(service: ApplyService) -> Router {
         .route("/groups/{id}/triggers", get(group_triggers_handler))
         .route("/groups/{id}/routes", get(group_routes_handler))
         .route("/apps/{id}/suppressions", get(app_suppressions_handler))
+        .route("/groups/{id}/suppressions", get(group_suppressions_handler))
         .with_state(service)
 }
 
@@ -64,6 +65,26 @@ async fn app_suppressions_handler(
     Ok(Json(report))
 }
 
+/// Read-only §11 tail M1 suppression report for a group: the inherited templates
+/// it declines for its whole subtree (`target_kind`, `reference`). Viewer-tier
+/// `GroupScriptsRead`. Backs `pic suppress ls --group`.
+async fn group_suppressions_handler(
+    State(svc): State<ApplyService>,
+    Extension(principal): Extension<Principal>,
+    Path(id_or_slug): Path<String>,
+) -> Result<Json<Vec<SuppressionInfo>>, ApplyError> {
+    let group_id = resolve_group_id(svc.groups.as_ref(), &id_or_slug).await?;
+    require(
+        svc.authz.as_ref(),
+        &principal,
+        Capability::GroupScriptsRead(group_id),
+    )
+    .await
+    .map_err(map_authz)?;
+    let report = svc.suppression_report(ApplyOwner::Group(group_id)).await?;
+    Ok(Json(report))
+}
+
 /// Read-only §11 tail route-template report for a group: its own declared route
 /// templates (method, host, path, handler script, dispatch, enabled). Viewer-
 /// tier read. Backs `pic routes ls --group`.

crates/manager-core/src/apply_service.rs

@@ -1293,16 +1293,17 @@ impl ApplyService {
         // A group endpoint is reached by *inheritance* (a descendant app binds
         // it by name), never by its own route, so the "no route/trigger"
         // warning is noise for every group script — emit it for apps only.
-        if let ApplyOwner::App(app_id) = owner {
+        if let ApplyOwner::App(_) = owner {
             report
                 .warnings
                 .extend(unreachable_endpoint_warnings(bundle));
-            // §11 tail: a suppress reference that matches no inherited template
-            // silently does nothing — warn (typo guard), don't fail.
-            report
-                .warnings
-                .extend(self.dangling_suppress_warnings(app_id, bundle).await?);
         }
+        // §11 tail: a suppress reference that matches no inherited template (or
+        // only sealed ones) silently does nothing — warn (typo guard), don't
+        // fail. M1: runs for a group node too (it walks the group's own chain).
+        report
+            .warnings
+            .extend(self.dangling_suppress_warnings(owner, bundle).await?);
 
         self.reconcile_node_tx(
             &mut tx,
@@ -2151,39 +2152,52 @@ impl ApplyService {
     /// refs match an ancestor-group route's path.
     async fn dangling_suppress_warnings(
         &self,
-        app_id: AppId,
+        owner: ApplyOwner,
         bundle: &Bundle,
     ) -> Result<Vec<String>, ApplyError> {
         if bundle.suppress_triggers.is_empty() && bundle.suppress_routes.is_empty() {
             return Ok(Vec::new());
         }
-        // Inherited (ancestor-group) trigger handler names + route paths, each
-        // tagged with whether ANY matching template is un-sealed (i.e. actually
-        // suppressible). `bool_or(NOT sealed)` = true iff at least one match can
-        // be declined; false = every match is `sealed` (§11 tail), so the
-        // suppression is inert; absent = no inherited template at all (a typo).
+        // §11 tail M1: the set of templates a suppression can decline lives on
+        // the OWNER's chain — an app walks its ancestor groups (`CHAIN_LEVELS_CTE`
+        // bound to the app), a group walks itself + its ancestors
+        // (`GROUP_CHAIN_LEVELS_CTE` bound to the group). Both CTEs expose a
+        // `chain` view with a `group_owner` column, so the queries below are
+        // identical modulo which CTE + bind.
+        let (chain_cte, owner_uuid) = match owner {
+            ApplyOwner::App(a) => (CHAIN_LEVELS_CTE, a.into_inner()),
+            ApplyOwner::Group(g) => (
+                crate::config_resolver::GROUP_CHAIN_LEVELS_CTE,
+                g.into_inner(),
+            ),
+        };
+        // Inherited trigger handler names + route paths, each tagged with whether
+        // ANY matching template is un-sealed (i.e. actually suppressible).
+        // `bool_or(NOT sealed)` = true iff at least one match can be declined;
+        // false = every match is `sealed` (§11 tail), so the suppression is
+        // inert; absent = no inherited template at all (a typo).
         let trig_names: Vec<(String, bool)> = sqlx::query_as(&format!(
-            "{CHAIN_LEVELS_CTE} \
+            "{chain_cte} \
              SELECT LOWER(s.name), bool_or(NOT t.sealed) FROM triggers t \
              JOIN scripts s ON s.id = t.script_id \
              JOIN chain c ON t.group_id = c.group_owner \
              WHERE t.group_id IS NOT NULL \
              GROUP BY LOWER(s.name)",
         ))
-        .bind(app_id.into_inner())
+        .bind(owner_uuid)
         .fetch_all(&self.pool)
         .await
         .map_err(|e| ApplyError::Backend(e.to_string()))?;
         let inherited_handlers: HashMap<String, bool> = trig_names.into_iter().collect();
 
         let route_paths: Vec<(String, bool)> = sqlx::query_as(&format!(
-            "{CHAIN_LEVELS_CTE} \
+            "{chain_cte} \
              SELECT r.path, bool_or(NOT r.sealed) FROM routes r \
              JOIN chain c ON r.group_id = c.group_owner \
              WHERE r.group_id IS NOT NULL \
              GROUP BY r.path",
         ))
-        .bind(app_id.into_inner())
+        .bind(owner_uuid)
         .fetch_all(&self.pool)
         .await
         .map_err(|e| ApplyError::Backend(e.to_string()))?;