refactor: rename Planarchy to CapaKraken (branding only)

User-facing rename across 20 files:
- Layout title/meta: "CapaKraken — Resource & Capacity Planning"
- Sidebar logo: "CapaKraken" with "RESOURCE & CAPACITY PLANNING"
- Sign-in page: "CapaKraken Control Center", "Sign in to CapaKraken"
- PWA manifest: name + short_name
- PDF reports: footer text
- Install prompt: "Install CapaKraken"
- AI assistant system prompt
- Webhooks test payload
- Email subject lines
- Tooltips, descriptions, empty states

NOT changed (technical identifiers):
- Package names (@planarchy/*)
- Import paths
- Database names
- Docker container names
- localStorage keys
- Domain URLs
- CLAUDE.md

Co-Authored-By: claude-flow <ruv@ruv.net>

packages/api/src/router/webhook.ts

@@ -144,7 +144,7 @@ export const webhookRouter = createTRPCRouter({
         payload: {
           webhookId: wh.id,
           webhookName: wh.name,
-          message: "This is a test payload from Planarchy.",
+          message: "This is a test payload from CapaKraken.",
         },
       };