feat(extension): add popup toggle to hide Agent control hints (#81)

Add a per-browser "Control hints" switch to the popup that hides the in-page control overlay (status pill + orange glow, along with its input blocker) while the Agent controls a tab. Preference lives in chrome.storage.local (bsk_control_hints_hidden, default: shown) and is applied live in content scripts via storage.onChanged.

Both popup settings rows share a single Switch component; the hint copy lives in an info-icon tooltip.

Refs #62

packages/i18n/src/locales/en-US/extension.json

@@ -23,6 +23,9 @@
       "disabled": "Off"
     },
     "connectionToggleTitle": "BrowserSkill connection",
+    "controlHintsToggleTitle": "Control hints",
+    "controlHintsToggleHint": "Show the status pill and orange glow while the Agent controls a page.",
+    "controlHintsInfoLabel": "About control hints",
     "versionSkewWarning": "Extension protocol v{{extensionProtocol}}, daemon v{{daemonProtocol}}.",
     "upgradeAvailable": "Upgradable",
     "launcher": {

packages/i18n/src/locales/zh-CN/extension.json

@@ -23,6 +23,9 @@
       "disabled": "Off"
     },
     "connectionToggleTitle": "BrowserSkill 连接",
+    "controlHintsToggleTitle": "控制提示",
+    "controlHintsToggleHint": "Agent 控制页面时显示提示条和橙色闪光。",
+    "controlHintsInfoLabel": "控制提示说明",
     "versionSkewWarning": "扩展协议 v{{extensionProtocol}}，daemon 协议 v{{daemonProtocol}}。",
     "upgradeAvailable": "可升级",
     "launcher": {