Add application support teams with contacts

Replaces the legacy supportteams/appowners pair: supportteams
(teamname unique, teamurl ServiceNow link) + supportteamcontacts
(multiple named contacts with SSO per team, the people you reach out
to), applications.supportteamid intact. Migration 7d18 migrates each
legacy team owner into a contact, drops appowners, and has a validated
downgrade. New /api/supportteams CRUD (admin writes, import-mode
timestamps, teamname lookup), Support card on application detail,
contacts column on the list, and a settings management page.
IMPORT-API.md mapping updated to the concrete endpoints.

658 tests pass; live dev migration applied (24 teams / 24 contacts);
fresh-install and downgrade round-trips verified on scratch DBs.

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

frontend/src/views/applications/ApplicationForm.vue

@@ -154,7 +154,7 @@
 <script setup>
 import { ref, onMounted, computed } from 'vue'
 import { useRoute, useRouter } from 'vue-router'
-import { applicationsApi } from '../../api'
+import { applicationsApi, supportteamsApi } from '../../api'
 import { apiError } from '../../utils/apiError'
 
 const route = useRoute()
@@ -187,7 +187,7 @@ const supportTeams = ref([])
 onMounted(async () => {
   try {
     // Load support teams
-    const teamsRes = await applicationsApi.getSupportTeams()
+    const teamsRes = await supportteamsApi.list()
     supportTeams.value = teamsRes.data.data || []
 
     // Load application if editing
@@ -198,7 +198,7 @@ onMounted(async () => {
       form.value = {
         appname: app.appname || '',
         appdescription: app.appdescription || '',
-        supportteamid: app.supportteam?.supportteamid || '',
+        supportteamid: app.supportteamid || '',
         isinstallable: app.isinstallable || false,
         islicenced: app.islicenced || false,
         isprinter: app.isprinter || false,