Create "level-1.tscn" rough draft tilemap level

[TSherpa10]

Create a rough draft level-1.tscn tilemap level using the sample tileset linked.

BRANCH OFF OF TESTING

Inspiration? Hollow Knight, Geometry Dash 2.2, etc.

Make it more platform-heavy than most Metroidvanias, but still side-scrolly (moreso than Hollow Knight).

Let me know if you want to implement suggestions for complicated character movement (tweaks to speed and jump velocity, coyote time / snappy jumping, etc.)