Fix journey cluster defects + UX improvements across 7 clusters

P0 fixes (clean-start + route contracts):
- VexHub: fix migration 002 table name + add repair migration 003
- Gateway: add /console/admin and /api/v1/unknowns routes
- IDP: add platform.idp.admin scope to OAuth client + web config
- Risk: fix URL construction from authority to gateway base
- Unknowns: fix client path from /api/v1/scanner/unknowns to /api/v1/unknowns

P1 fixes (trust + shell integrity):
- Audit: fix module name normalization, add Authority audit source
- Stage: add persistence across web store, API contracts, DB migration 059
- Posture: add per-source error tracking + degradation banner

P2 fixes (adoption + workflow clarity):
- Rename Triage to Findings in navigation + breadcrumbs
- Command palette: show quick actions for plain text queries, fix scan routes
- Scan: add local-mode limitation messaging + queue hints
- Release: add post-seal promotion CTA with pre-filled release ID
- Welcome: rewrite around operator adoption model (Get Started + What Stella Replaces)

UX improvements:
- Status rail: convert to icon-only with color state + tooltips
- Event Stream Monitor: new page at /ops/operations/event-stream
- Sidebar: collapse Operations by default
- User menu: embed theme switcher (Day/Night/System), remove standalone toggle
- Settings: add Profile section with email editing + PUT /api/v1/platform/preferences/email endpoint
- Docs viewer: replace custom parser with ngx-markdown (marked) for proper table/code/blockquote rendering

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

devops/compose/postgres-init/04-authority-schema.sql

@@ -657,6 +657,7 @@ VALUES
             'export.viewer', 'export.operator', 'export.admin',
             'vuln:view', 'vuln:investigate', 'vuln:operate', 'vuln:audit',
             'platform.context.read', 'platform.context.write',
+            'platform.idp.read', 'platform.idp.admin',
             'doctor:run', 'doctor:admin', 'ops.health',
             'integration:read', 'integration:write', 'integration:operate', 'registry.admin',
             'timeline:read', 'timeline:write',