Phase 007: migrate every remaining view from naive-ui to Arco Design Vue

The project now has exactly one UI library. Every naive-ui component in
packages/client/src is replaced by its Arco equivalent across 24 views and
roughly 80 components, and naive-ui is dropped from package.json along with
its transitive vueuc / @css-render / vdirs / seemly dependencies.

The migration is rendering-layer only. No store logic, no API contract, and
no /chat-run payload was touched.

Three classes of leftover were invisible to `grep naive-ui` and are now
covered by tests/client/no-naive-ui.test.ts, which asserts all three:
  - dead .n-* class names in style blocks
  - dead --n-* custom properties
  - naive-ui in package.json

Notable behavioural traps handled along the way, recorded in
docs/arco-migration-rules.md:
  - a-input-password defaults to masked; passing default-visibility="false"
    would have exposed API keys in clear text
  - a-upload fires a real XHR unless auto-upload is false
  - nested Trigger components fight over the first element child, so the
    group-chat settings dropdown was flattened
  - Arco renders tooltip default-slot text inline, which was silently
    collapsing the chat and group-chat toolbars

docs/chat-chain-changes/2026-10-18-phase007-arco-full-migration.md

@@ -0,0 +1,73 @@
+---
+date: 2026-10-18
+pr: pending
+feature: Phase 007 - full naive-ui to Arco Design Vue migration across all remaining views
+impact: Rendering-layer only. Every naive-ui component in packages/client/src is replaced by its Arco Design Vue equivalent across 24 views and roughly 80 components, and the naive-ui dependency is removed from package.json and package-lock.json. No chat store logic, no /chat-run payload, and no message rendering path is touched. Three chat-chain files changed as a consequence of that rendering-only sweep, listed below with the specific reason each needed a change.
+---
+
+# Phase 007 — full Arco migration
+
+Phase 006 moved the chat page. Phase 007 finished the job: `grep -rn "naive-ui\|vueuc\|@css-render" packages/client/src` is now empty, and the project has exactly one UI library.
+
+Batches 7a-7g each shipped independently per `docs/phases/phase_007.md`. `docs/arco-migration-rules.md` holds the component mapping table the whole sweep followed.
+
+## Why chat-chain files changed
+
+Four files under the chat chain were caught by the sweep. None of the changes touch logic.
+
+### `chat/ChatPanel.vue`
+
+- Three leftover naive CSS custom properties were still referenced: `--n-text-color-3` (twice)
+  and `--n-color-hover` (once). These were dead after Phase 006 — the variables no longer
+  resolve, so the rules silently did nothing. Rewritten to the project's own tokens
+  (`--text-muted`, `--bg-card-hover`).
+- `:native-scrollbar="false"` on the workspace dropdown had no Arco counterpart and was
+  dropped.
+
+### `group-chat/GroupChatInput.vue`
+
+- Eighteen dead naive rules under `.tool-trace-toggle`, `.input-settings-button` and
+  `.send-button` targeted `.n-button__content`, `.n-button__icon`, `.n-button__border`,
+  `.n-button__state-border`, `.n-button__ripple` and `.n-base-wave`. Arco's `a-button` has
+  no content wrapper and none of the ripple internals, so `gap` now lives on the button
+  itself and the ripple rules were deleted rather than renamed.
+- The settings button was `NDropdown > NTooltip > NButton` — a three-deep Trigger nest.
+  Arco's Trigger components each claim the first element child via `mergeFirstChild`, so
+  nested popups fight over it and the menu never opens. Flattened to `a-dropdown > a-button`
+  with the description moved to a native `:title`, which is the same approach Phase 006
+  already took in `ChatInput.vue`.
+- The attach tooltip carried its label as trailing default-slot text. Arco renders the
+  default slot inline, so that text became a zero-width flex item in the toolbar. Moved to
+  the `content` prop.
+
+### `group-chat/CreateRoomForm.vue`
+
+- Straight component swap. `InputLikeInstance = { focus: () => void }` was kept because
+  Arco's `a-input` still exposes `focus()` (`es/input/input.js:315`), so the existing
+  `nextTick` focus calls still work.
+
+### `group-chat/GroupChatPanel.vue`
+
+- The room context menu was `NDropdown` in `trigger="manual"` mode driven by `:x` / `:y` /
+  `:show` / `@clickoutside`. Arco has no manual trigger, so it became
+  `a-trigger trigger="contextMenu"` with `:popup-style` for coordinates, matching the
+  pattern already used by `FileContextMenu.vue` and `WorkflowView.vue`. Arco's
+  `clickOutsideToClose` defaults to true, which replaces the hand-written clickoutside
+  handler.
+- `NPopover`'s `placement="bottom-end"` maps to Arco `position="br"` (bottom-right).
+  Arco's `a-popover` has no `width` prop and its `Trigger` sets `inheritAttrs: false`, so a
+  `:width` would be dropped silently; the width moved to `:content-style`.
+
+## Verification
+
+`packages/client/src` has zero naive references by three independent checks — `naive-ui`
+imports, `.n-*` class names in style blocks, and `--n-*` custom properties. The last two
+matter because `grep naive-ui` cannot see them; `tests/client/no-naive-ui.test.ts` now
+guards all three so the patterns cannot come back.
+
+## Behavior impact
+
+Rendering-layer only. No chat store logic, no `/chat-run` payload, and no message rendering
+path was touched. The group-chat message bubbles already used plain HTML and were left
+untouched, so the "no Arco components inside bubbles" rule still holds — `a-tree`, `a-select`
+and the other components appear only outside the bubble.