Restructure CCP Metrics to metric-first hierarchy, fix Jira cross-project sync

CCP Metrics View Restructure:
- Add GET /metrics endpoint (aggregated across verticals)
- Add GET /metric/:id/verticals endpoint (per-vertical breakdown)
- Replace VerticalTable with MetricTable on overview (one row per metric)
- Add MetricDetailView for metric-first drill-down
- Restructure navigation: Metric → Vertical → Subteam → Devices
- Remove By Vertical table from AggregatedBurndownChart

Jira Sync Fix:
- Remove hardcoded project filter from getIssue() and searchIssuesByKeys()
- Issue keys are globally unique; project filter broke cross-project tickets
- Fixes 502 Bad Gateway when syncing tickets from non-STEAM projects

backend/helpers/jiraApi.js

@@ -276,7 +276,9 @@ function jiraDelete(urlPath, options) {
  * @param {string[]} [fields] - Jira field names to return
  */
 async function getIssue(issueKey, fields) {
-    const jql = `key = "${issueKey}" AND project = ${JIRA_PROJECT_KEY}`;
+    // Don't filter by project — issue keys are globally unique in Jira and
+    // tickets may belong to projects other than JIRA_PROJECT_KEY (e.g. AA_ADTRAN).
+    const jql = `key = "${issueKey}"`;
     const result = await searchIssues(jql, { fields: fields || DEFAULT_FIELDS, maxResults: 1, startAt: 0 });
     if (result.ok && result.data.issues && result.data.issues.length > 0) {
         return { ok: true, data: result.data.issues[0] };
@@ -300,11 +302,10 @@ async function searchIssuesByKeys(issueKeys, opts) {
         return { ok: true, data: { total: 0, issues: [] } };
     }
 
-    // Build JQL: key in (KEY-1, KEY-2, ...) — Charter requires project+updated
-    // or similar, but key-based search is inherently scoped. We add updated
-    // clause for compliance.
+    // Build JQL: key in (KEY-1, KEY-2, ...) — issue keys are globally unique,
+    // so no project filter needed. Add updated clause for Charter compliance.
     const keyList = issueKeys.map(k => `"${k}"`).join(', ');
-    const jql = `key in (${keyList}) AND updated >= -72h AND project = ${JIRA_PROJECT_KEY}`;
+    const jql = `key in (${keyList}) AND updated >= -72h`;
     const fields = (opts && opts.fields) || DEFAULT_FIELDS;
     const maxResults = Math.min((opts && opts.maxResults) || 1000, 1000);