Refactor ServerCard stack to use id-based callbacks

Distinguishes server `id` (the unique map key in MCPConfig.mcpServers)
from `name` (display label) so containers can dispatch by id without
relying on display strings. ServerCard, ConnectionToggle, ServerListScreen,
and supporting stories all updated.

- ServerCard: add `id` prop; all action callbacks now `(id: string) => void`
- ConnectionToggle: collapse `onConnect`/`onDisconnect` into single `onToggle`
- ServerListScreen: lift `activeServer` to a prop; combine `onSetActive` +
  `onToggleConnection` into a single `onToggleConnection(id)` callback
- Stories: use UUIDs for server ids so callbacks visibly carry ids, not names

Removes the "Direct"/"Via Proxy" connection mode concept, which is no
longer planned. ServerSettingsForm drops the section, ServerCard drops
the badge, InspectorServerSettings drops the field.

Removes the "Test Client Features" dropdown from ServerCard along with
its four handlers; that surface will live elsewhere.

TransportBadge now collapses `sse` and `streamable-http` into a single
"HTTP" label; ServerCard adds a grey transport descriptor next to the
badge ("Standard I/O", "SSE (Server Sent Events) [deprecated]",
"Streamable HTTP"). The version badge moves from the header row to sit
beside the transport badge.

ServerCard header no longer wraps; long server names truncate with
ellipsis.

Specification docs (`v2_scope.md`, `v2_screenshots.md`,
`v2_ux_interfaces.md`, `v2_ux_storybook.md`) updated to match.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

specification/v2_scope.md

@@ -49,10 +49,6 @@
   * SSE  
   * SHTTP  
 
-## Connection Type
-  * Direct   
-  * Via Proxy  
-
 ## Logging Level Control
   * Present and synchronized when connecting to server with logging capability