refactor(tests+frontend): one http_sink helper for the hook tests; apiErrorMessage replaces ten hand-rolled error-body parses; type X, import specifiers are not definitions (#2904, milestone 299 step 6)

tests/helpers.http_sink replaces three module-local _Sink handlers (the
write-path tests and the after-write test). ProjectView + SettingsView
parsed `(e as {body?:{error?}}).body?.error || fallback` by hand ten times
beside the apiErrorMessage canon (#2853) - all ten now call it. The
extractor (server + the hook awk mirror) no longer reads `import { type Foo }`
as a definition of Foo - that was the last "identical body" sym family.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

frontend/src/views/ProjectView.vue

@@ -1,7 +1,7 @@
 <script setup lang="ts">
 import { ref, computed, onMounted, watch } from "vue";
 import { useRoute, useRouter } from "vue-router";
-import { apiGet, apiPatch, apiDelete, apiPost, apiPut } from "@/api/client";
+import { apiGet, apiPatch, apiDelete, apiPost, apiPut, apiErrorMessage } from "@/api/client";
 import { useAuthStore } from "@/stores/auth";
 import { useToastStore } from "@/stores/toast";
 import { useTasksStore } from "@/stores/tasks";
@@ -543,8 +543,7 @@ async function saveForgePin() {
     if (project.value) project.value.forge_connection_id = forgePin.value;
     await loadCoverage();
   } catch (e) {
-    const body = (e as { body?: { error?: string } }).body;
-    toast.show(body?.error || "Failed to change the project's forge", "error");
+    toast.show(apiErrorMessage(e, "Failed to change the project's forge"), "error");
     forgePin.value = project.value?.forge_connection_id ?? null;
   } finally {
     savingForgePin.value = false;

frontend/src/views/SettingsView.vue

@@ -780,8 +780,7 @@ async function saveConnection() {
     connFormOpen.value = false;
     await loadForgeConnections();
   } catch (e) {
-    const body = (e as { body?: { error?: string } }).body;
-    toastStore.show(body?.error || "Failed to save forge connection", "error");
+    toastStore.show(apiErrorMessage(e, "Failed to save forge connection"), "error");
   } finally {
     savingConn.value = false;
   }
@@ -793,8 +792,7 @@ async function removeConnection(id: number) {
     connTestResult.value = null;
     await loadForgeConnections();
   } catch (e) {
-    const body = (e as { body?: { error?: string } }).body;
-    toastStore.show(body?.error || "Failed to delete forge connection", "error");
+    toastStore.show(apiErrorMessage(e, "Failed to delete forge connection"), "error");
   }
 }
 
@@ -810,10 +808,9 @@ async function testConnection(id: number) {
       message: `Connected — ${res.version}, authenticated as ${res.username}`,
     };
   } catch (e) {
-    const body = (e as { body?: { error?: string } }).body;
     connTestResult.value = {
       id, ok: false,
-      message: body?.error || "Connection test failed",
+      message: apiErrorMessage(e, "Connection test failed"),
     };
   } finally {
     testingConnId.value = 0;
@@ -830,8 +827,7 @@ async function saveForgeWebhook() {
     forgeWebhookSaved.value = true;
     setTimeout(() => (forgeWebhookSaved.value = false), 2000);
   } catch (e) {
-    const body = (e as { body?: { error?: string } }).body;
-    toastStore.show(body?.error || "Failed to save webhook secret", "error");
+    toastStore.show(apiErrorMessage(e, "Failed to save webhook secret"), "error");
   } finally {
     savingForgeWebhook.value = false;
   }
@@ -864,8 +860,7 @@ async function saveMarketplaceUrl() {
     marketplaceUrlSaved.value = true;
     setTimeout(() => (marketplaceUrlSaved.value = false), 2000);
   } catch (e) {
-    const body = (e as { body?: { error?: string } }).body;
-    toastStore.show(body?.error || "Failed to save marketplace URL", "error");
+    toastStore.show(apiErrorMessage(e, "Failed to save marketplace URL"), "error");
   } finally {
     savingMarketplaceUrl.value = false;
   }
@@ -882,8 +877,7 @@ async function saveDbMaintenance() {
     dbMaintSaved.value = true;
     setTimeout(() => (dbMaintSaved.value = false), 2000);
   } catch (e) {
-    const body = (e as { body?: { error?: string } }).body;
-    toastStore.show(body?.error || "Failed to save maintenance settings", "error");
+    toastStore.show(apiErrorMessage(e, "Failed to save maintenance settings"), "error");
   } finally {
     savingDbMaint.value = false;
   }
@@ -912,8 +906,7 @@ async function runDbMaintenanceNow() {
     );
     await loadDbHealth(); // reflect the dead-tuple drop
   } catch (e) {
-    const body = (e as { body?: { error?: string } }).body;
-    toastStore.show(body?.error || "Maintenance run failed", "error");
+    toastStore.show(apiErrorMessage(e, "Maintenance run failed"), "error");
   } finally {
     runningDbMaint.value = false;
   }
@@ -1144,8 +1137,7 @@ async function sendInvite() {
     inviteEmail.value = "";
     await fetchInvitations();
   } catch (e: unknown) {
-    const body = (e as { body?: { error?: string } })?.body;
-    toastStore.show(body?.error || "Failed to send invitation", "error");
+    toastStore.show(apiErrorMessage(e, "Failed to send invitation"), "error");
   } finally {
     sendingInvite.value = false;
   }
@@ -1196,8 +1188,7 @@ async function deleteUser(userId: number) {
     users.value = users.value.filter((u) => u.id !== userId);
     toastStore.show("User deleted");
   } catch (e: unknown) {
-    const body = (e as { body?: { error?: string } })?.body;
-    toastStore.show(body?.error || "Failed to delete user", "error");
+    toastStore.show(apiErrorMessage(e, "Failed to delete user"), "error");
   } finally {
     deleting.value = null;
   }