Initial commit: move CLI (milestone 2)

- src/move.ts entry point with CLI parsing, --help, --version
- src/cli.ts: parseCliArgs, printHelp, ParsedCliArgs, CliError, VERSION
- src/config.ts: Config type, DEFAULT_CONFIG, resolveConfig
- src/keeper.ts: synthetic-activity sweep + idle-watch loop
- package.json bin entry + shebang for 'bun link' global install
- install.sh: contributor bootstrap (will be repurposed; see
  DISTRIBUTION-PLAN.md for the end-user installer design)
- DISTRIBUTION-PLAN.md captures the tabled end-user distribution work

install.sh

@@ -0,0 +1,41 @@
+#!/usr/bin/env bash
+#
+# install.sh - bootstrap the Teams Status Keeper project.
+#
+# Verifies Bun is installed, then runs `bun install` to fetch dependencies
+# (notably `@nut-tree-fork/nut-js`, which ships prebuilt native binaries
+# for darwin-arm64/x64, linux, and windows).
+#
+# This script is idempotent: re-running it just re-resolves the dependency
+# tree against the existing `bun.lock`.
+
+# Fail fast on any error, unset variable, or failed pipe stage.
+set -euo pipefail
+
+# Always operate relative to the script's own directory so the install works
+# regardless of the caller's CWD.
+cd "$(dirname "$0")"
+
+echo "==> Checking for Bun..."
+if ! command -v bun >/dev/null 2>&1; then
+    # Hard error rather than auto-install: keep the script's behavior
+    # predictable and let the user pick their own install method.
+    echo "Error: bun is not installed." >&2
+    echo "       Install it from https://bun.sh (e.g. 'brew install oven-sh/bun/bun') and re-run." >&2
+    exit 1
+fi
+echo "    bun $(bun --version)"
+
+echo "==> Installing dependencies..."
+bun install
+
+echo
+echo "Done. Run with: bun run start"
+
+# macOS gates synthetic mouse events behind the Accessibility permission.
+# Without this hint, the first run silently fails to move the cursor and
+# the user has no obvious next step.
+if [[ "$(uname)" == "Darwin" ]]; then
+    echo "Note: macOS will prompt for Accessibility permission on first mouse move."
+    echo "      Grant it under System Settings > Privacy & Security > Accessibility."
+fi