logs: replace every fmt::print with a lg call instead (#1368)

Favors the `lg` namespace over `fmt` directly, as this will output the
logs to a file / has log levels.

I also made assertion errors go to a file, this unfortunately means
importing `lg` and hence `fmt` which was attempted to be avoided before.
But I'm not sure how else to do this aspect without re-inventing the
file logging.

We have a lot of commented out prints as well that we should probably
cleanup at some point / switch them to trace level and default to `info`
level.

I noticed the pattern of disabling debug logs behind some boolean,
something to consider cleaning up in the future -- if our logs were more
structured (knowing where they are coming from) then a lot this
boilerplate could be eliminated.

Closes #1358

common/custom_data/pack_helpers.cpp

@@ -2,13 +2,15 @@
 
 #include <map>
 
+#include "common/log/log.h"
+
 constexpr float kClusterSize = 4096 * 40;  // 100 in-game meters
 constexpr float kMasterOffset = 12000 * 4096;
 
 std::pair<u64, u16> position_to_cluster_and_offset(float in) {
   in += kMasterOffset;
   if (in < 0) {
-    fmt::print("negative: {}\n", in);
+    lg::print("negative: {}\n", in);
   }
   ASSERT(in >= 0);
   int cluster_cell = (in / kClusterSize);
@@ -69,4 +71,4 @@ void pack_tfrag_vertices(tfrag3::PackedTfragVertices* result,
   }
 
   ASSERT(next_cluster_idx < UINT16_MAX);
-}
+}