fix(ui): surface resume-planning-session failures

ResumePlanningSessionAsync wrapped everything in an empty catch, so a
failed resume vanished silently. Report it via the footer error channel
with a dedicated planningResumeFailed message.

src/ClaudeDo.Localization/locales/en.json

@@ -210,6 +210,7 @@
       "addedSummary": "✓ Added {0} ({1} file(s))",
       "overLimitError": "Could not add {0}: {1}",
       "invalidNameError": "Could not add {0}: {1}",
+      "dropReadError": "Couldn't read the dropped files: {0}",
       "selectIdleTask": "Select an idle task first"
     },
     "sections": {
@@ -505,7 +506,7 @@
     "taskStatus": { "idle": "Idle", "queued": "Queued", "running": "Running", "waitingForReview": "Waiting for Review", "waitingForChildren": "Waiting for Subtasks", "done": "Done", "failed": "Failed", "cancelled": "Cancelled", "parked": "Parked" },
     "planningBadge": { "active": "PLANNING", "finalized": "PLANNED" },
     "taskRow": { "createdPrefix": "Created {0}", "stepsText": "{0}/{1} steps" },
-    "tasksIsland": { "completedHeader": "COMPLETED", "completedHeaderCount": "COMPLETED · {0}", "planningOpenFailed": "Couldn't open planning session: {0}", "pickUpInTerminalFailed": "Pick up in terminal failed: {0}", "approveFailed": "Approve & merge failed: {0}" },
+    "tasksIsland": { "completedHeader": "COMPLETED", "completedHeaderCount": "COMPLETED · {0}", "planningOpenFailed": "Couldn't open planning session: {0}", "planningResumeFailed": "Couldn't resume planning session: {0}", "pickUpInTerminalFailed": "Pick up in terminal failed: {0}", "approveFailed": "Approve & merge failed: {0}" },
     "diff": { "loadFailed": "Failed to load diff: {0}", "noChanges": "No changes to show.", "unavailable": "Diff no longer available — commit range incomplete." },
     "planningDiff": { "hubError": "Could not build combined preview (hub error).", "conflict": "Cannot build combined preview: subtask {0} conflicts with an earlier subtask ({1} files)." },
     "merge": { "commitMessage": "Merge task: {0}", "workerOfflineBranches": "Worker offline — cannot list branches.", "loadBranchesFailed": "Failed to load branches: {0}", "merged": "Merged.", "conflict": "Merge conflict — target branch restored. Resolve manually or via Continue, then retry.", "blocked": "Blocked: {0}", "unknownStatus": "Unknown status: {0}", "mergeFailed": "Merge failed: {0}" },