Enforce strict ESLint block formatting - #185

Summary

• Add @stylistic/eslint-plugin and enforce curly braces, multiline object literals, multiline block braces, and blank lines between consecutive control-flow blocks.
• Format the existing SDK source and tests to satisfy the new policy.
• Add focused ESLint configuration tests covering valid formatting and each required violation.
• Add root script-test discovery and a narrow ESLint override for the new Node-based config test.

The installed Stylistic v5 schema does not accept { always: true } for object-curly-newline; the equivalent supported configuration uses ObjectExpression: { minProperties: 1 }, preserving the requested behavior for non-empty object literals while remaining compatible with Prettier.

Validation

• npm run lint
• npm test — 27 files / 351 tests
• npm run build