Deliver Docker App snapshots through managed volumes

[adityathakker]

Summary

• replace App snapshot host bind mounts with a managed named volume
• transfer snapshots to stopped App containers with Docker archive copy before start
• clean up App containers, volumes, networks, and port allocations on all failure paths

Verification

• node --experimental-test-module-mocks --test test/docker-deploy-provider.test.ts
• npm run typecheck
• npm run lint
• npm run format:check
• git diff --check

The provider change is intentionally generic and contains no organization-specific integration.

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