Add official TypeScript client

[starboyate]

Summary

• Add the official @openmemind/memind TypeScript client package with typed models, request validation, retry handling, timeout support, and structured API errors.
• Add TypeScript client tests, build tooling, package metadata, README examples, and npm pack validation.
• Add CI and release workflows for the TypeScript client, and update root documentation and Maven license exclusions for the npm package workspace.
• Remove the local superpowers design spec from the feature branch so it is not included in the PR.

Test Plan

• pnpm format:check
• pnpm lint
• pnpm typecheck
• pnpm test (75 tests passed)
• pnpm build
• pnpm pack:check
• mvn clean install -Dmaven.test.skip=true
• mvn test (33 reactor modules succeeded)

Release Notes

• The npm package is configured as public under @openmemind/memind.
• GitHub Actions publishing uses npm provenance for trusted CI releases.