codebase-layoutlisted

# Codebase layout A session placing a new file copies the folder next to it, so a flat folder stays flat until a refactor pays to split it. In one target, two source folders grew to 46 and 36 flat files under installed rules against it, and the split cost a pull request touching 98 files. This skill carries the placement call to the moment the path is written, which is the one moment it is cheap. Load it before writing a new path into a plan, not after. A worker copies the path the plan gives it, so the placement is settled once the plan is. Skip it when every path the work names already exists. ## Read the project's strategy first - Name the layout the project already uses before placing anything: by feature, by route, by role, or flat. Look at the folders a new file would sit beside and at any stated rule on layout. - Keep to that strategy. A second strategy beside the first costs every later reader a guess about which one a file follows. - Propose a strategy change as its own decision, never as a side effect of placing one file. ## Group what changes together - Put files that change for the same reason in one folder, and separate files that change for different reasons. - Name a folder for what it holds for a reader, being a feature, a route, or a role, over its technical kind alone. `checkout/` tells a reader what is inside where `helpers/` does not. - Never create a bucket named `misc`, `common`, `utils`, or `helpers` on its own. Qualify it by what it serves, or p