Wire INTEGRATION_SECRET into docker-compose and CI; archive komoot-import

- Add INTEGRATION_SECRET to journal service in docker-compose.yml with
  :? guard so a missing value fails loudly at compose-up time
- Add INTEGRATION_SECRET to E2E test step in ci.yml via GitHub secret
  (unit tests already set their own value in the test file)
- Archive openspec/changes/komoot-import → archive/2026-05-23-komoot-import
- Sync delta specs: new openspec/specs/komoot-import/spec.md,
  updated openspec/specs/route-management/spec.md

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

infrastructure/docker-compose.yml

@@ -48,6 +48,7 @@ services:
       WAHOO_CLIENT_ID: ${WAHOO_CLIENT_ID:-}
       WAHOO_CLIENT_SECRET: ${WAHOO_CLIENT_SECRET:-}
       WAHOO_WEBHOOK_TOKEN: ${WAHOO_WEBHOOK_TOKEN:-}
+      INTEGRATION_SECRET: ${INTEGRATION_SECRET:?INTEGRATION_SECRET must be set in SOPS secrets.app.env}
       # Demo-activity-bot. Disabled by default everywhere; flip to "true"
       # only in prod. When unset, DEMO_BOT_PERSONA uses the built-in
       # Bruno/Berlin persona. See docs/demo-persona.md for the schema.