fix(sjdb): off-by-one on stitch-time acceptor coordinate

The previous commit normalised the DB to genome-absolute 0-based and
updated the stats-time query. Stitch-time was left unchanged on the
assumption that it already passed genome-absolute 0-based — half right.
donor_fwd was correct (first intron base, 0-based) but acceptor_fwd =
donor_fwd + del landed on the first base AFTER the intron, while the
DB keys store the last intron base. Lookup missed every annotated
junction.

Subtract 1 from the acceptor to land on the last intron base. After
this, Log.final.out Annotated (sjdb) goes from 0 to a non-zero count
that's consistent with the annotated=1 row count in SJ.out.tab on
the same BAM.

Co-Authored-By: Claude <noreply@anthropic.com>

Author: pinin4fjords

src/align/stitch.rs

@@ -1302,12 +1302,11 @@ fn stitch_align_to_transcript(
                 return None;
             }
 
-            // Check annotation (needed for sjdbScore bonus and finalization check)
             let is_annotated = junction_db.is_some_and(|db| {
                 let junc_donor_sa = (donor_sa as i64 + jr_shift as i64) as u64;
                 let donor_fwd =
                     index.sa_pos_to_forward(junc_donor_sa, cluster.is_reverse, del as usize);
-                let acceptor_fwd = donor_fwd + del as u64;
+                let acceptor_fwd = donor_fwd + del as u64 - 1;
                 db.is_annotated(cluster.chr_idx, donor_fwd, acceptor_fwd, 0)
                     || db.is_annotated(cluster.chr_idx, donor_fwd, acceptor_fwd, 1)
                     || db.is_annotated(cluster.chr_idx, donor_fwd, acceptor_fwd, 2)