fix(client): restore typecheck and image attachment preview modal

[Bob-Swan]

Summary

• Added image attachment preview modal wiring in the composition flow.
• Preserved explicit remove behavior on attachment overlay (X) click.
• Fixed client TypeScript blockers in Native settings and Theme store typings.
• Removed missing @testing-library/jest-dom type entry from client tsconfig.
• Aligned i18n dynamic catalog import path and annotated generated JS import.

Validation

• Ran: pnpm exec tsc -p tsconfig.json --noEmit (workdir: packages/client)
• Result: pass

[Bob-Swan]

Hi maintainers, Bob here.

I pushed a follow-up update to satisfy DCO (Signed-off-by added) and kept the patch scoped to client typecheck/image-preview behavior only.

Validation run locally:

• pnpm exec tsc -p tsconfig.json --noEmit in packages/client (pass)

If preferred, I can split UI preview behavior and type-safety fixes into separate PRs.

[Bob-Swan]

Quick follow-up: all required checks are now green (DCO + PR title).

Could a maintainer please review this when available? Happy to make any requested changes quickly.