fix: preserve mobile jump hosts

[ZacharyZcR]

Refs Termix-SSH/Support#422

Summary

• normalize jumpHosts returned by the server before Mobile uses host records
• preserve existing jump-host chains when editing a host from Mobile
• preserve jump-host chains when cloning hosts

Validation

• npx eslint --quiet app/main-axios.ts app/tabs/hosts/HostForm.tsx app/tabs/hosts/Hosts.tsx
• git diff --check

Notes

• npm run lint still fails on pre-existing settings screen issues outside this change.
• npx tsc --noEmit still fails on pre-existing app/tabs/settings/KeyboardCustomization.tsx type issue outside this change.