fix: add json parse error handler

[7eliassen]

Adds explicit handling for JSON parsing errors in the global error handler. When a request contains invalid JSON, the server now returns a consistent 400 Bad Request response instead of falling through to generic error handling.

[github-actions]

Coverage Report

Status	Category	Percentage	Covered / Total
🔵	Lines	85.82% (🎯 80%) ⬇️ -0.09%	8938 / 10414
🔵	Statements	85.82% (🎯 80%) ⬇️ -0.09%	8938 / 10414
🔵	Functions	79.53% (🎯 80%) 🟰 ±0%	276 / 347
🔵	Branches	84.28% (🎯 80%) ⬇️ -0.29%	445 / 528

File Coverage

File	Stmts	Branches	Functions	Lines	Uncovered Lines
Changed Files
src/presentation/http/http-api.ts	93.45% ⬇️ -2.61%	85.29% ⬇️ -5.03%	93.75% 🟰 ±0%	93.45% ⬇️ -2.61%	103-111, 122-123, 325-326, 349-350, 380-390

Generated in workflow #912 for commit f322e19 by the Vitest Coverage Report Action

[Copilot]

Pull request overview

Adds explicit handling for invalid JSON request bodies in the Fastify global error handler, aiming to return a consistent 400 response instead of delegating to generic error handling.

Changes:

• Import StatusCodes for standardized HTTP status constants.
• Add a SyntaxError handling branch in setErrorHandler that logs and returns a 400 JSON response for invalid JSON bodies.

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[Copilot]

The JSON-parse branch matches any SyntaxError whose message contains "JSON", which can inadvertently convert server-side JSON.parse bugs into 400 responses and make them harder to detect. Consider narrowing the condition to Fastify body-parser errors (e.g., check error.statusCode === 400 and/or a Fastify-specific error.code/body marker) so only invalid request bodies are handled here.

Suggested change

	* JSON parse errors (invalid request body)
	*/
	if (error instanceof SyntaxError && error.message.includes('JSON')) {
	* JSON parse errors from Fastify body parser (invalid request body)
	*/
	if (
	(error as any)?.statusCode === StatusCodes.BAD_REQUEST &&
	typeof (error as any)?.code === 'string' &&
	(error as any).code.startsWith('FST_ERR_CTP_')
	) {

[Copilot]

This 400 response body includes error and statusCode, but other API error helpers in this codebase (e.g., reply.domainError, reply.unauthorized, etc.) return { message }, and ErrorResponse only defines code/message (src/presentation/http/types/HttpResponse.ts). To keep client error handling consistent, consider sending the same shape here (likely just { message }, or { code, message } if you want an app-level code).

Suggested change

	error: 'Bad Request',
	statusCode: StatusCodes.BAD_REQUEST,

[Copilot]

New behavior in the global error handler should be covered by tests. There is existing Vitest coverage for HTTP routes using global.api.fakeRequest (e.g., src/presentation/http/router/*.test.ts); please add a test that sends invalid JSON with content-type: application/json and asserts the API returns 400 with the expected error payload.