fix: use origin/ ref when branching from default branch (#149)

resolve_default_branch returns a bare branch name (e.g. "main") which
points to the local branch. After git fetch, origin/main is up to date
but the local main may be stale — causing new worktrees to start from
an old commit.

The resolved_ref logic in create_worktree compounds this: it tries
git rev-parse "main^{commit}" first, which succeeds with the stale
local SHA, so the origin/ fallback never runs.

Prefix with origin/ so new branches always start from the latest remote.

Author: averyjennings

lib/commands/create.sh

@@ -73,12 +73,12 @@ _create_resolve_from_ref() {
       from_ref=$(get_current_branch)
       if [ -z "$from_ref" ] || [ "$from_ref" = "HEAD" ]; then
         log_warn "Currently in detached HEAD state - falling back to default branch"
-        from_ref=$(resolve_default_branch "$repo_root")
+        from_ref="origin/$(resolve_default_branch "$repo_root")"
       else
         log_info "Creating from current branch: $from_ref"
       fi
     else
-      from_ref=$(resolve_default_branch "$repo_root")
+      from_ref="origin/$(resolve_default_branch "$repo_root")"
     fi
   fi