feat(worker,data): persist interactive session id so a closed/aborted ConPTY session can be resumed

Generates the claude session id up front (--session-id <guid>) for a fresh interactive task
session and persists it to TaskEntity.InteractiveSessionId before launch, so an abort at any
point still leaves a resumable id. BuildForTaskAsync now resumes this task's own last
interactive session in preference to the latest autonomous run's session, but never across a
freshly (re)created worktree.

src/ClaudeDo.Worker/Runner/Interfaces/IInteractiveLaunchSpecService.cs

@@ -17,9 +17,12 @@ public interface IInteractiveLaunchSpecService
     /// Throws KeyNotFoundException if the task doesn't exist, InvalidOperationException
     /// if it's Running/Queued. If the task has no usable worktree yet, one is created on
     /// demand (same mechanism as an autonomous run) provided the task's list has a working
-    /// directory pointing at a git repo -- otherwise throws InvalidOperationException. A task
-    /// that has never run, or whose worktree was just created fresh, gets a fresh-start spec
-    /// (no --resume); an existing worktree with a persisted SessionId gets --resume.</summary>
+    /// directory pointing at a git repo -- otherwise throws InvalidOperationException. Resumes
+    /// (--resume) this task's own last interactive session (TaskEntity.InteractiveSessionId) if
+    /// it has one, else the latest autonomous run's session; a task that has never run either
+    /// way, or whose worktree was just created fresh, gets a fresh-start spec instead -- pre-
+    /// assigned a new session id via --session-id and persisted to InteractiveSessionId before
+    /// launch, so a closed/aborted session can be resumed next time.</summary>
     Task<LaunchSpec> BuildForTaskAsync(string taskId, CancellationToken ct);
 
     /// <summary>Builds a LaunchSpec for an ad-hoc interactive session in an arbitrary directory --