The earlier dry-run change moved scope into an options object, silently
ignoring the legacy uninstallPlugin(id, "user") runtime shape still reachable
from compiled or plain-JS callers. Restore scope as the positional second
argument and carry dryRun in a trailing options bag, preserving the existing
call shape while keeping the non-mutating dry-run path.
Fixes#8178
Route marketplace dry-runs through MarketplaceManager's normal pre-mutation
validation so ambiguous or mismatched scopes fail exactly as real uninstalls
do. Move the manager's scope argument into an options object and add a dry-run
option that returns only after all removal planning has succeeded.
Fixes#8178
handleUninstall dropped the parsed dryRun flag and unconditionally called
mktMgr.uninstallPlugin / manager.uninstall, so `omp plugin uninstall
<plugin> --dry-run` removed the plugin on both the marketplace and npm
routes. Propagate dryRun into handleUninstall and short-circuit before
both removal calls, reporting the resolved removal (with its source)
instead of mutating state.
Fixes#8178
roboomp