Integrate the Commander adapter with master's `dsh web --workspace-root`
(workspace-aware session flow).
- args.ts: add `--workspace-root <path>` to the web subcommand; WebInvocation
carries workspaceRoot.
- web.ts: keep the adapter-parsed signature, take (host, port, dev,
workspaceRoot) and pass workspaceRoot through to AppCLIEntry (drop master's
re-added parseArgs and CLI host/port validation — the schema owns those).
- bin.ts forwards invocation.workspaceRoot; args.spec + the Agent Note pair note
the flag.