CB-576: hasUncommitted tolerates an already-gone worktree

bridged/src/main/java/dev/ltms/bridged/session/GitWorktrees.java

@@ -169,6 +169,14 @@ public final class GitWorktrees implements Worktrees {
 
     @Override
     public boolean hasUncommitted(String worktreePath) {
+        // A worktree that is already gone holds no work to lose, and it must not break teardown:
+        // git -C <missing-dir> status exits non-zero and would throw where release() is mid-way
+        // through stopping a pane. Mirror remove()'s already-gone tolerance by treating it as clean.
+        Path p = Path.of(worktreePath);
+        if (!Files.exists(p)) {
+            log.debug("worktree {} already gone — nothing can be uncommitted", worktreePath);
+            return false;
+        }
         // No --untracked-files=no: the exact shape of the work lost in CB-576 was a new file
         // that was never added, so an untracked-only worktree is still dirty.
         String out = exec("git", "-C", worktreePath, "status", "--porcelain");

bridged/src/main/java/dev/ltms/bridged/session/Worktrees.java

@@ -15,6 +15,10 @@ public interface Worktrees {
      * modifications, staged files, or untracked files. {@code git status --porcelain} is the
      * test; an empty result means clean. Callers use this to decide whether removing the
      * worktree would silently destroy a worker's only copy of its work.
+     *
+     * <p>An already-gone worktree is reported as clean (no throw), matching {@link #remove}'s
+     * idempotent contract: a path that does not exist holds no work to lose, and must not break
+     * a teardown that is mid-way through stopping the pane.
      */
     boolean hasUncommitted(String worktreePath);