Add pinnable new-tab targets to the tab row and sidebar

Any new-tab target (new agent, terminal, browser, or a terminal profile)
can be pinned as a quick-launch button. Pins are global client app state
(persisted), not daemon config, so the same set shows on every workspace;
profile pins resolve per host and are dropped where that profile is absent.

The sidebar mirror launches via a navigate-then-launch intent store rather
than calling the create handlers directly: terminal creation only works in
the mounted/focused workspace, so the sidebar requests the launch and the
workspace screen consumes it on focus.

packages/app/src/i18n/resources/fr.ts

@@ -471,6 +471,8 @@ export const fr: TranslationResources = {
         splitDown: "Diviser le volet vers le bas",
         terminalProfilesMenu: "Terminal profiles",
         editTerminalProfiles: "Edit profiles…",
+        pinTarget: "Épingler",
+        unpinTarget: "Détacher",
       },
       explorer: {
         open: "Ouvrir l'explorateur",