Completions: provided by engines break right at the start of a newline

[Druue]

Bug description

This was found in the process of adding the new schemas autocompletion for the datasource block and does not affect the other completion that engines provides.
relevant pr

---

When even a single character after the initial, schemas is available for autocompletion

However, this breaks on the initial character of a newline - @tomhoule suggested it being due to the \n newline character being treated as part of the previous line within our spans.

How to reproduce

Expected behavior

This should be able to trigger engines completions from anywhere on a new line, not just after the initial character

Prisma information

generator client {
    provider        = "prisma-client-js"
    previewFeatures = ["multiSchema"]
}

datasource db {
    provider = "postgres"
    url      = env("DATABASE_URL")

}

Environment & setup

• OS: MacOS
• Database: Any connector that supports MultiSchema

Prisma Version

Insiders