Introduce a new OOBE step for "Startup & Presentation" that exposes startup and UI preferences in OobeWindow (toggles for taskbar, slide/fade transitions, fused popup, and autostart). Add HostAppSettingsOobeMerger to read/write Host settings.json (PascalCase fields) and MergeStartupPresentation behavior, plus LauncherWindowsStartupService to sync the current Launcher into the Windows Run key on Windows. Wire UI handlers, persist choices on Next, and load defaults when entering the step. Include unit tests for the merger, adjust SettingsWindow navigation pane/toggle handling, and update docs/LAUNCHER.md to describe the new OOBE step and implementation files.
Introduce a per-user OOBE state model and hardened launch/elevation handling. Adds OobeStateFile/OobeLaunchDecision models, OobeStateService (persisting %LOCALAPPDATA%/.launcher/state/oobe-state.json), and LauncherExecutionContext to capture elevation and user SID. CommandContext now normalizes/infers launch-source values (normal, postinstall, apply-update, plugin-install, debug-preview) and exposes maintenance checks. LauncherFlowCoordinator propagates richer launcher context details for diagnostics and suppresses OOBE for elevated/maintenance contexts. PluginInstallerService avoids requesting elevation for user-scoped installs and returns a clear error when installation target is outside the current user's LocalAppData. LauncherClient maps and surfaces result codes, UpdateWorkflow and installer invocation now pass explicit --launch-source values, and WelcomeOobeStep persists OOBE completion via the new service. Adds unit tests (CommandContext, OobeStateService, PluginInstallerService), docs/specs/checklists for the contract, and makes internals visible to tests.
