fix(web): remove mantine-border-animate, use green highlight border (#1536)

* fix(web): remove mantine-border-animate, use green highlight border (#1535)

The @gfazioli/mantine-border-animate dependency emitted a persistent
React "forwardRef render functions accept exactly two parameters"
warning on every page load. Remove the dependency entirely and replace
the freshly-added card's animated border with a green border.

- Drop @gfazioli/mantine-border-animate from clients/web (package + lock)
  and remove its styles.css import from main.tsx.
- Add a `highlighted` variant to the Card theme that draws a 2px green
  border, driven by a new --inspector-highlight-border token in App.css.
- ServerCard now selects the variant (disabled > highlighted) instead of
  wrapping in BorderAnimate; the BorderAnimate flex-wrapper `w="100%"`
  workaround is no longer needed.
- Update ServerCard/ServerListScreen tests to assert the highlighted
  variant instead of the removed BorderAnimate DOM.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

* refactor(web): drop redundant Card props on ServerCard (#1535)

ThemeCard.defaultProps already sets withBorder and padding="lg", so the
explicit props on ServerCard's <Card> were redundant. Addresses review
feedback on PR #1536.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

* docs(web): note highlighted Card variant relies on inherited withBorder (#1535)

Addresses a maintainability flag from the PR #1536 re-review: the
highlighted variant only sets borderColor/borderWidth and depends on the
withBorder:true default, so make that coupling explicit in a comment.

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

clients/web/package.json

@@ -36,7 +36,6 @@
     "@dnd-kit/sortable": "^8.0.0",
     "@dnd-kit/utilities": "^3.2.2",
     "@emotion/react": "^11.14.0",
-    "@gfazioli/mantine-border-animate": "^2.0.3",
     "@hono/node-server": "^1.19.14",
     "@mantine/core": "^8.3.17",
     "@mantine/form": "^8.3.17",