v2.3.0

Friendly, localized error handling; mobile and deploy improvements.

- In-app error toasts now show calm, human, localized messages instead of raw
  chain assertions, mapping the common Blurt transaction errors (with a generic
  fallback) across all nine locales.
- Fix long error messages overflowing the viewport on mobile.
- Remove the obsolete out-of-bandwidth / Resource Credits modal, which does not
  apply to Blurt (transactions are gated by fees, not a resource-credit allowance).
- Version the per-environment deploy config in the repo so the deploy jobs ship it.

Classification: MINOR — user-facing features and fixes, no breaking changes.