feat(ui): label streamed installs as not shareable

NEXT_STEPS item 7 needed the installed-but-not-downloaded state to be
clear to users. Keep streamed installs in the installed visual state so
sorting, filters, and the primary Play action stay unchanged, but make the
sharing limitation visible in the UI.

Cards now label that state as `Not shareable`, while the detail modal
status says `Installed, not shareable`. Downloaded-and-installed games
keep the normal `Installed` wording.

Test Plan:
- just frontend-test
- just build
- git diff --check
- git diff --cached --check

Refs: NEXT_STEPS.md item 7

crates/lanspread-tauri-deno-ts/tests/gameState.test.ts

@@ -11,7 +11,9 @@ import {
     formatDownloadEta,
     formatDownloadSpeed,
     formatDownloadSpeedShort,
+    gameStatusLabel,
     mergeGameUpdate,
+    stateChipLabel,
 } from '../src/lib/gameState.ts';
 import {
     ActiveOperationKind,
@@ -243,3 +245,42 @@ Deno.test('stream install is available only for idle remote games', () => {
         'busy games should not expose streamed install',
     );
 });
+
+Deno.test('streamed local installs are labeled installed but not shareable', () => {
+    const streamed = game({
+        downloaded: false,
+        installed: true,
+        install_status: InstallStatus.Installed,
+    });
+    const downloadedInstall = game({
+        downloaded: true,
+        installed: true,
+        install_status: InstallStatus.Installed,
+    });
+
+    assertEquals(
+        deriveState(streamed),
+        'installed',
+        'streamed local installs should keep installed visual state',
+    );
+    assertEquals(
+        stateChipLabel(streamed),
+        'Not shareable',
+        'card chip should make the non-shareable state visible',
+    );
+    assertEquals(
+        gameStatusLabel(streamed),
+        'Installed, not shareable',
+        'detail status should spell out installed plus non-shareable',
+    );
+    assertEquals(
+        stateChipLabel(downloadedInstall),
+        'Installed',
+        'normal downloaded installs should keep the installed chip label',
+    );
+    assertEquals(
+        gameStatusLabel(downloadedInstall),
+        'Installed',
+        'normal downloaded installs should keep the installed detail label',
+    );
+});