feat(export-import): add yaml export/import with id upsert for credentials, snippets, and scenarios

- all entities export a kind field (credential/snippet/scenario) for safe type checking on import
- import upserts by id: overwrites if id exists, creates with explicit id otherwise
- scenario export now includes id and step ids; import deletes old steps before recreating
- add GET /:id/export and POST /import endpoints to credential and snippet controllers
- add UuidBadge ui component: shortens uuid to first+last 4 hex chars, tooltip, clipboard copy with animated ClipboardCheck icon pop
- apply UuidBadge across all entity id display sites (detail pages, card footers, table columns)
- add export/import buttons to CredentialsPage, SnippetsPage, CredentialDetailPage, SnippetDetailPage

client/src/pages/run/RunDetailPage.tsx

@@ -21,6 +21,7 @@ import {
   Notification,
   Table,
   Timestamp,
+  UuidBadge,
   type TableColumn,
 } from '../../ui';
 import type { BadgeVariant } from '../../ui';
@@ -82,7 +83,7 @@ export function RunDetailPage() {
     if (!id || !runId) return;
     let cancelled = false;
 
-    Promise.all([scenarios.get(Number(id)), runs.get(Number(id), Number(runId))])
+    Promise.all([scenarios.get(id), runs.get(id, runId)])
       .then(([sc, r]) => {
         if (cancelled) return;
         setScenario(sc);
@@ -91,7 +92,7 @@ export function RunDetailPage() {
           setPolling(true);
           pollRef.current = setInterval(async () => {
             try {
-              const updated = await runs.get(Number(id), Number(runId));
+              const updated = await runs.get(id, runId);
               if (cancelled) return;
               setRun(updated);
               setPulseKey((k) => k + 1);
@@ -183,7 +184,7 @@ export function RunDetailPage() {
             <DescriptionList
               layout="comfortable"
               items={[
-                { term: t('runs.field_id'), detail: run.id },
+                { term: t('runs.field_id'), detail: <UuidBadge id={run.id} /> },
                 {
                   term: t('runs.field_status'),
                   detail: (