refactor: hide git repo path details from more packages (#38601)

Remove `RepoPath` from "models/repo" package, remove `UserPath` from
"models/user" package, use `WithRepo` for more places, fine tune tests.

routers/web/repo/githttp.go

@@ -24,6 +24,7 @@ import (
 	"gitea.dev/models/unit"
 	"gitea.dev/modules/git"
 	"gitea.dev/modules/git/gitcmd"
+	"gitea.dev/modules/git/gitrepo"
 	"gitea.dev/modules/log"
 	repo_module "gitea.dev/modules/repository"
 	"gitea.dev/modules/setting"
@@ -342,7 +343,7 @@ func (h *serviceHandler) sendFile(ctx *context.Context, contentType, file string
 		return
 	}
 
-	fs := git.GetRepoFS(h.getStorageRepo())
+	fs := gitrepo.RepoLocalFS(h.getStorageRepo())
 	ctx.Resp.Header().Set("Content-Type", contentType)
 	http.ServeFileFS(ctx.Resp, ctx.Req, fs, path.Clean(file))
 }