87: bug 01 refactor to match design documents

[semere-meb]

Summary

Refactors classes to match design documents.

Fixes #87

Changes

• Change Parser -> ConfigLoader
• Parser.get_config() -> ConfigLoader.load()
• Adapter -> MazeAdapter
• Updated test cases to reflect these changes
• new Maze class to represent the visual maze

Testing

• make lint passes locally
• make test passes locally (check N/A below if no tests exist yet for this area)
• Manually tested the behavior described above
• N/A — no automated tests apply to this change yet

Checklist

• PR title follows <TICKET-ID>: short description
• Linked to the correct issue (Fixes #... above)
• No unrelated changes bundled into this diff
• Updated docs/design/ if this changes config shape, architecture, or a game-design decision
• Updated README if this changes user-facing behavior (config keys, controls, etc.)