More fixes

server-rs/src/data/poi.rs

@@ -23,7 +23,7 @@ pub struct POIData {
     /// Byte offset into `id_buffer` where each row's ID starts.
     id_offsets: Vec<u32>,
     /// Length in bytes of each row's ID.
-    id_lengths: Vec<u8>,
+    id_lengths: Vec<u16>,
     pub group: InternedColumn,
     pub category: InternedColumn,
     pub name: Vec<String>,
@@ -101,7 +101,7 @@ impl POIData {
         let mut id_lengths = Vec::with_capacity(row_count);
         for s in &id_raw {
             let offset = id_buffer.len() as u32;
-            let length = s.len().min(u8::MAX as usize) as u8;
+            let length = s.len().min(u16::MAX as usize) as u16;
             id_offsets.push(offset);
             id_lengths.push(length);
             id_buffer.push_str(&s[..length as usize]);

server-rs/src/data/postcodes.rs

@@ -128,6 +128,7 @@ impl PostcodeData {
                     // Compute centroid across all vertices from all rings
                     let total_vertices: usize = rings.iter().map(|ring| ring.len()).sum();
                     let centroid = if total_vertices == 0 {
+                        tracing::warn!(postcode = %postcode, "Postcode polygon has zero vertices, defaulting centroid to (0,0)");
                         (0.0, 0.0)
                     } else {
                         let mut sum_lat: f32 = 0.0;