34160032fc
Replace the flat `remotes:` map (with `type: "remote"/"virtual"/"local"`) with separate top-level sections — `remote:`, `virtual:`, `local:` — so the repo type is declared structurally and the `type:` field is no longer needed. Config loader normalises the new format to the existing internal representation (injecting `type` into each remote dict), so all handler code is unchanged. Adds a TestYamlTypeKeys suite covering all three type keys, mixed files, and field preservation. Includes README migration guide for splitting a single remotes file into per-type-and-package conf.d files.