Preserve requested adb reinstall mode as replace_requested and report replaced as null when no prior package-state observation exists. Keep install Success/Failure, raw output and host digest, with an explicit Evidence limitation; add no device queries.
Validation: stateful CLI fake distinguishes fresh/existing installs and checks exact version/install commands, plus provider and MCP schema controls. No real-device verification claimed.
Fixes#3166
BREAKING CHANGE: install_adb_package now requires replace_requested and exposes replaced as nullable rather than claiming the selected mode was an observed replacement.