feat: show bytes in human readable format

[lemmih]

Summary of changes

Changes introduced in this pull request:

• Show bytes in human-readable format.
• Include total size when available.

Before:

$ cargo run --bin forest-tool -- snapshot fetch --chain calibnet
2023-12-13T11:14:17.386015Z  INFO forest::snapshot: downloading snapshot url=https://forest-archive.chainsafe.dev/latest/calibnet/
2023-12-13T11:14:23.333352Z  INFO forest::progress: Loading 122474496 (elapsed time: 5s)
2023-12-13T11:14:28.351351Z  INFO forest::progress: Loading 246546432 (elapsed time: 10s)
2023-12-13T11:14:33.371548Z  INFO forest::progress: Loading 369876992 (elapsed time: 15s)
2023-12-13T11:14:38.371557Z  INFO forest::progress: Loading 495095808 (elapsed time: 20s)

After:

$ cargo run --bin forest-tool -- snapshot fetch --chain calibnet
2023-12-13T11:11:45.398062Z  INFO forest::snapshot: downloading snapshot url=https://forest-archive.chainsafe.dev/latest/calibnet/
2023-12-13T11:11:52.218596Z  INFO forest::progress: Loading 115.6 MiB / 2.7 GiB, 4%, 115.6 MiB/s, elapsed time: 5s
2023-12-13T11:11:57.218769Z  INFO forest::progress: Loading 232.5 MiB / 2.7 GiB, 8%, 117 MiB/s, elapsed time: 10s
2023-12-13T11:12:02.230479Z  INFO forest::progress: Loading 343.6 MiB / 2.7 GiB, 12%, 111.1 MiB/s, elapsed time: 15s
2023-12-13T11:12:07.230596Z  INFO forest::progress: Loading 459.4 MiB / 2.7 GiB, 16%, 115.8 MiB/s, elapsed time: 20s

Before:

2023-12-13T11:20:53.492928Z  INFO forest_filecoin::chain_sync::chain_muxer: Local node is behind the network, starting BOOTSTRAP from LOCAL_HEAD = 1128407 -> NETWORK_HEAD = 1171335
2023-12-13T11:20:58.695216Z  INFO forest::progress: Downloading headers 613 (elapsed time: 5s)
2023-12-13T11:21:03.781629Z  INFO forest::progress: Downloading headers 1228 (elapsed time: 10s)
2023-12-13T11:21:09.223284Z  INFO forest::progress: Downloading headers 1843 (elapsed time: 15s)
2023-12-13T11:21:14.946055Z  INFO forest::progress: Downloading headers 2356 (elapsed time: 21s)

After:

023-12-13T11:19:46.107371Z  INFO forest_filecoin::chain_sync::chain_muxer: Local node is behind the network, starting BOOTSTRAP from LOCAL_HEAD = 1128407 -> NETWORK_HEAD = 1171333
2023-12-13T11:19:51.242939Z  INFO forest::progress: Downloading headers 714, 714 items/s, elapsed time: 5s
2023-12-13T11:19:56.833518Z  INFO forest::progress: Downloading headers 1433, 719 items/s, elapsed time: 10s
2023-12-13T11:20:02.541617Z  INFO forest::progress: Downloading headers 2149, 716 items/s, elapsed time: 16s
2023-12-13T11:20:08.072752Z  INFO forest::progress: Downloading headers 2657, 508 items/s, elapsed time: 21s

Reference issue to close (if applicable)

Closes

Other information and links

Change checklist

• I have performed a self-review of my own code,
• I have made corresponding changes to the documentation,
• I have added tests that prove my fix is effective or that my feature works (if possible),
• I have made sure the CHANGELOG is up-to-date. All user-facing changes should be reflected in this document.

[LesnyRumcajs]

rock solid, with tests and all