Merge branch 'master' into claude/unified-environment-credentials-c8841a

Master removed the TUI package, the `meta` and `upgrade` subcommands, and
`--config-replace`, and made raw `dsh` require a `--config` overlay. Resolved
onto that shape:

- Dropped this branch's TUI edits with the surface itself, including
  `tui.cordis.yml`, `runTui`, and the TUI keyless PTY smoke.
- Dropped the `--config-replace` plumbing rather than reintroducing a flag
  master deliberately removed. The gap this branch fixed remains: `dsh -p`
  still could not name its composition, so it keeps `--config`.
- Kept this branch's deletion of the personal `$DSH_HOME/config.yaml` layer,
  which master still carried, and provided the environment snapshot in the new
  raw `runConfig` surface alongside web and headless.
- Ported the headless shutdown PTY test off the personal overlay onto a named
  `--config` file, which is what proves that flag now exists on `-p`.

apps/cli/README.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 apps/cli/README.md
-README.md: 3195fb4856ec794186658afd5e329cd58e6a3b28
-README.zh.md: 011cacb347aff88f6a04544dcd9b5e9b8d434c18
+README.md: 190a68f9e9bc9a2fea09b94afff55351aa6362de
+README.zh.md: b0560bd579ddba871cd9851f54b310abbaac8d1c