fix: set authenticated user on request context in bearer token auth

tryBearerAuth validated the bearer token but never looked up the
associated user or set it on the request context. This meant
downstream handlers calling GetCurrentUser would get nil even
with a valid token.

Changes:
- Add ContextWithUser/UserFromContext helpers in auth package
- tryBearerAuth now looks up the user by token's UserID and
  sets it on the request context via auth.ContextWithUser
- GetCurrentUser checks context first before falling back to
  session cookie
- Add integration tests for bearer auth user context

internal/service/deploy/deploy.go

@@ -82,7 +82,7 @@ type deploymentLogWriter struct {
 	lineBuffer bytes.Buffer // buffer for incomplete lines
 	mu         sync.Mutex
 	done       chan struct{}
-	flushed    sync.WaitGroup // waits for flush goroutine to finish
+	flushed    sync.WaitGroup  // waits for flush goroutine to finish
 	flushCtx   context.Context //nolint:containedctx // needed for async flush goroutine
 }