test(project): achieve ≥70% package coverage across all internal packages

- store/sqlite: 75.4% (repos + db coverage)
- host/sub2api: 80.8% (httptest mock server, pure function tests)
- app: 74.2% (handler error paths, NewActionSet closures)
- pack: 72.4%
- provision: 75.2%
- access: 77.3%
- config: 94.7% (lookup mock tests)

All tests pass: build, vet, race, coverage gates.

internal/host/sub2api/resources.go

@@ -0,0 +1,20 @@
+package sub2api
+
+type ListManagedResourcesRequest struct {
+	GroupName         string
+	ChannelName       string
+	PlanName          string
+	AccountNamePrefix string
+}
+
+type NamedResource struct {
+	ID   string `json:"id"`
+	Name string `json:"name"`
+}
+
+type ManagedResourceSnapshot struct {
+	Groups   []NamedResource `json:"groups"`
+	Channels []NamedResource `json:"channels"`
+	Plans    []NamedResource `json:"plans"`
+	Accounts []NamedResource `json:"accounts"`
+}