D52 — .cartographer.yaml always machine-wide (home): project/global scope removed

Context. Every client subcommand and the TUI had a --global/g flag/key to choose between .cartographer.yaml in the cwd or in the home. The project scope was never used: the connection to a server is a property of the machine, not of the repo in which the command runs.

Decision. .cartographer.yaml/the lockfile always live in ~/. clientconfig. TargetDir() no longer takes a global parameter. Removed everywhere: the --global flag, the g key in the TUI, the global parameter from printApplySummary/autoTrustCommand.

Discarded alternatives. Keeping the flag with a true default (it would have left a dead project-scope codepath to maintain for no benefit). Details: docs/configurator.md §.cartographer.yaml.