feat(cc-config): edit settings.json values from the dashboard

Replace the batch multi-key settings.json editor with a recursive per-leaf
editor: each scalar value gets its own inline edit control, the dotted path
is rebuilt from the node's ancestry, and a redacted value renders as a
static non-editable chip. Saves go straight through the existing
PATCH /api/cc-config/settings per-key merge.

client/src/i18n/locales/en/ccConfig.json

@@ -331,12 +331,12 @@
     "settingsKeyPlaceholder": "key or dotted.path",
     "settingsValue": "Value (JSON)",
     "settingsAddKey": "Add key",
-    "settingsRemoveKey": "Remove key",
     "settingsEmptyKey": "A key name cannot be empty.",
-    "settingsDupKey": "Key {{key}} is listed twice.",
     "settingsBadJson": "Value of {{key}} is not valid JSON.",
-    "settingsSaved": "Settings saved to {{file}}.",
-    "settingsHelp": "Values are JSON: \"opus\", true, 42, [\"a\"], {\"k\":1}. Only the keys you change are written; the rest of the file is left as-is.",
-    "settingsRedactedKeys": "Not editable here because their values are redacted: {{keys}}"
+    "editKey": "Edit {{key}}",
+    "settingsKeySaved": "Saved {{key}} · backup at {{backup}}",
+    "settingsLastBackup": "Saved {{key}} · backup at {{backup}}",
+    "settingsRedactedTooltip": "The dashboard never received this value.",
+    "settingsRedactedChip": "redacted"
   }
 }