refactor(ui): remove pick-up-in-terminal, keep ConPTY as the single session entry

Two context-menu entries opened a Claude session for the same task via different
mechanisms (embedded ConPTY vs. an external wt terminal). Drop the external-terminal
path entirely, including its worker hub method, launcher plumbing, and localization
keys, since the embedded ConPTY session already covers every case it did.

src/ClaudeDo.Worker/Runner/InteractiveLaunchSpecService.cs

@@ -14,8 +14,9 @@ namespace ClaudeDo.Worker.Runner;
 // session-skills seeded onto disk (reuses ISessionSkillSeeder + TaskRunner.UnionSkillNames,
 // exactly like TaskRunner.RunAsync/ContinueAsync) and the same run environment variables
 // (reuses ClaudeProcess's MCP_TOOL_TIMEOUT). Exe/Args reuse WindowsTerminalLauncher's
-// --resume argument construction. Guards mirror WorkerHub.ResumeTaskInTerminal, except a
-// never-run task (no persisted SessionId) is not an error here -- it's a fresh-start spec.
+// --resume argument construction. Guards: no running/queued task, and (once a worktree
+// exists) it must be live on disk -- but a never-run task (no persisted SessionId) is not
+// an error here, it's a fresh-start spec.
 //
 // The run-scoped "claudedo_run" MCP server (AskUser/SuggestImprovement) that TaskRunner
 // wires per headless run is intentionally NOT reused: it exists so an unattended run can