fix(i18n): replace hardcoded UI labels with locale keys

Add missing en/ru translations and wire reports, agent, git, settings,
mapper, and tasks surfaces so UI copy follows the active locale.

frontend/src/lib/i18n/locales/en/tasks.json

@@ -100,5 +100,14 @@
   "auto_scroll": "Auto-scroll",
   "auto_scroll_on": "on",
   "auto_scroll_off": "off",
-  "result": "Check"
+  "result": "Check",
+  "clear": "Clear",
+  "clear_title": "Clear tasks?",
+  "failure_cause": "Failure cause",
+  "llm_summary": "LLM summary",
+  "name": "Task Name",
+  "open_task_drawer": "View task",
+  "runner_subtitle": "Task execution monitoring",
+  "runner_empty_hint": "Start a mapping task to see logs and execution details",
+  "log_quick_filters_aria": "Log quick filters"
 }