Fix track ids containing '\n' not decoding properly

This has been the cause of the elusive "selecting a track opens it like an index" bug :)

src/tangara/database/records.cpp

@@ -19,6 +19,7 @@
 
 #include "cppbor.h"
 #include "cppbor_parse.h"
+#include "debug.hpp"
 #include "esp_log.h"
 
 #include "database/index.hpp"
@@ -229,16 +230,16 @@ auto ParseIndexKey(const leveldb::Slice& slice) -> std::optional<IndexKey> {
   std::istringstream in(key_data.substr(header_length + 1));
   std::stringbuf buffer{};
 
+  // FIXME: what if the item contains a '\0'? Probably we make a big mess.
   in.get(buffer, kFieldSeparator);
   if (buffer.str().size() > 0) {
     result.item = buffer.str();
   }
 
-  buffer = {};
+  std::string id_str =
-  in.get(buffer);
+      key_data.substr(header_length + 1 + buffer.str().size() + 1);
-  std::string id_str = buffer.str();
   if (id_str.size() > 1) {
-    result.track = BytesToTrackId(id_str.substr(1));
+    result.track = BytesToTrackId(id_str);
   }
 
   return result;
@@ -252,6 +253,7 @@ auto BytesToTrackId(std::span<const char> bytes) -> std::optional<TrackId> {
   auto [res, unused, err] = cppbor::parse(
       reinterpret_cast<const uint8_t*>(bytes.data()), bytes.size());
   if (!res || res->type() != cppbor::UINT) {
+    ESP_LOGE(kTag, "Track ID parsing failed!!");
     return {};
   }
   return res->asUint()->unsignedValue();

src/util/include/debug.hpp

@@ -31,8 +31,8 @@ inline std::string format_hex_string(std::span<const std::byte> data) {
       oss << " ";
     }
     int byte_val = (int)byte;
-    oss << "[0x" << std::uppercase << std::setfill('0') << std::setw(2)
+    oss << std::uppercase << std::setfill('0') << std::setw(2) << std::hex
-        << std::hex << byte_val << ']';
+        << byte_val << ' ';
     if (byte_val >= 32 && byte_val < 127) {
       ascii_values << (char)byte;
     } else {