Phase 005: vendor ArkScope, land the Arco style baseline, and fix bridge interpreter resolution

- Vendor ArkScope decorative layers (ScrambleTitle / IsometricWave) with provenance notes; decorative-only per AGENTS.md red lines
- Migrate theme tokens to Arco, register the Arco theme, and add hook adapter composables (useMessage / useDialog / useNotification) with matching signatures
- Sample pages: LoginView and AppSidebar on the new baseline; docs/arco-mapping.md and docs/ui-baseline.md land
- agent-bridge: prefer the PM-selected venv from facts.json over legacy in-tree venvs (legacy lacks the mcp extra, so every MCP server showed 0 tools / not connected)
- agent-bridge python (vendored, deliberate deviation): MCP discovery import fallback and pyyaml -> hermes_yaml so plugins and MCP work under the PM env; install the mcp extra via `hermes pm install --extra mcp`
- Chat-chain fragment: docs/chat-chain-changes/2026-10-17-phase005-arkscope-baseline.md

Verified: harness:check, test (2020 passed), test:e2e (30 passed), build all green; manual: plugins 100/0 warnings, MCP 6/6 servers connected with 104 tools.

packages/client/src/components/hermes/settings/DisplaySettings.vue

@@ -1,6 +1,7 @@
 <script setup lang="ts">
 import { computed } from 'vue'
-import { NButton, NSwitch, NSelect, NInputNumber, useMessage } from 'naive-ui'
+import { NButton, NSwitch, NSelect, NInputNumber } from 'naive-ui'
+import { useMessage } from '@/composables/useMessage'
 import { useI18n } from 'vue-i18n'
 import { useSettingsStore } from '@/stores/hermes/settings'
 import { useTheme, type BrightnessMode } from '@/composables/useTheme'