refactor(cli): bail early in the arg adapter instead of returning errors as data

Address review and cut ceremony: the adapter no longer models help/version/
errors as DshInvocation members. Commander owns those under exitOverride — it
prints usage or the diagnostic and one try/catch in parseDshArgs turns the
thrown CommanderError into process.exit with the intended code. bin.ts drops its
help/version/error cases; the union is the three real modes.

Domain checks bail via command.error(print + exit 1): --prompt rejects an empty
task or a stray config/--resume, empty --resume= fails loud, and --host/--port
are validated. A repeated --resume or a flag captured as a value is Commander's
standard behavior, left alone (a bad id fails loud downstream). dsh --help
discloses web via addHelpText. Net: args.ts 185 -> 112 lines.

Also fixes review nits: built-bin e2e resolves on `close`; the /resume handoff
uses `dsh --resume=<id> -- <config>` so a config named `web` stays a positional;
and stale prose (cordis.yml comment, app-boot module doc + duplicate JSDoc,
ui/README, two feature notes, an agent-loop test name) tracks the shipped state.
Removes tui-demo's now-dead plugin-include dep and vendor/loader + app-boot
tsconfig references.

.agents/notes/implemented/feature/2026-07-21-dsh-system-prompt-source-path.i18n.yaml

@@ -2,5 +2,5 @@
 # side as of the last confirmed-consistent state. Both languages carry equal authority;
 # after editing either side, bring the other along and re-record with:
 #   pnpm run verify-translation-pairing --write
-2026-07-21-dsh-system-prompt-source-path.md: b54d01488fd7c0b49e06200c93af2b056c9fd00b
-2026-07-21-dsh-system-prompt-source-path.zh.md: 208e3dce072f63c280999e15276dce62ff4e5c43
+2026-07-21-dsh-system-prompt-source-path.md: 4cb89e8124840bba6633235d195e95957245137c
+2026-07-21-dsh-system-prompt-source-path.zh.md: 90c23bed4a3f95155e323c63a68fe2da09543ea6