feat(browser): rework element annotation and picker toolbar

Element annotation is now free-text: dropped the Fix/Change/Question/
Approve intent pills and the intent field, so the user just says what
they want. The card uses the shared Button and is titled "Annotate
element".

Toolbar: the element picker and DevTools are no longer dev-gated and
work in prod; DevTools uses a wrench icon, and the old clipboard "grab"
is now a Camera "Screenshot element" tool. Each toolbar button
highlights only its own mode, and the copy toast reflects whether a
screenshot image was actually captured.

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

@@ -422,22 +422,17 @@ export const en = {
         enterUrl: "Enter URL",
         openDevTools: "Open browser dev tools",
         cancelSelector: "Cancel element selector",
-        selectElement: "Select element",
-        grabElement: "Copy element to clipboard",
-        grabElementLabel: "element",
-        grabFailed: "Couldn't copy element",
+        annotateElement: "Annotate element",
+        screenshotElement: "Screenshot element",
+        screenshotCopied: "Copied screenshot to clipboard",
+        elementCopied: "Copied element to clipboard",
+        screenshotFailed: "Couldn't copy screenshot",
       },
       annotate: {
-        title: "Send feedback to agent",
-        placeholder: "Describe what should change…",
+        title: "Annotate element",
+        placeholder: "Message to the agent about this element…",
         submit: "Attach",
         cancel: "Cancel",
-        intents: {
-          fix: "Fix",
-          change: "Change",
-          question: "Question",
-          approve: "Approve",
-        },
       },
       devices: {
         label: "Device size",