Add developer-only fake-client scripts and UI actions for testing proxy behavior. Files updated: server/fake_player.py, server/dev_server_app.py, server/README.md, docs/dev-log.md. New scripts/actions: Walk Circle, Jump Once, Toggle Sneak, Leave Cell (Left Cell), Return To Cell, and Teleport Test. UI: added buttons and handlers in the DevServerWindow to trigger these actions. fake_player: implemented script/state handling, one-shot jump thread, teleport toggle, sneak flag, walk-circle movement, cell change transforms, a socket send lock, and protection for one-shot/action state. README and dev log updated with usage, testing notes, and known issues. Basic headless smoke tests and py_compile checks were performed; full in-game Fallout 4/F4SE validation remains manual.