Phase 002: rebrand to hermes-ui and consolidate i18n to zh/en

Removes the ekko / hermes-web-ui branding from the whole tree and drops
eight locale files, so the project presents one name and one language pair.

Data compatibility is deliberate, not accidental: DB filenames, the JWT
audience, and skill manifest ownership all still recognise their pre-rename
values so existing deployments under ~/.hermes-web-ui keep working without a
re-login or a re-injection.

scripts/harness-check.mjs now scans for the legacy strings and fails the
build on any new occurrence, with an explicit allow-list (and reasons) for
the compatibility paths that must keep them.

tests/client/login-view.test.ts

@@ -117,8 +117,8 @@ describe('LoginView password login', () => {
     expect(wrapper.find('.login-lock-hint').text()).toContain('login.defaultLoginResetHint')
     const commands = wrapper.findAll('.login-lock-hint code').map(command => command.text())
     expect(commands).toEqual([
-      'hermes-web-ui clear-login-locks --restart',
-      'hermes-web-ui reset-default-login',
+      'hermes-ui clear-login-locks --restart',
+      'hermes-ui reset-default-login',
     ])
   })