wip: smol datatypes

[teh-cmc]

Blocked on:

• Reduce the overhead of DataTypes jorgecarleitao/arrow2#1469
• Update to latest arrow2 + new datatypes DataEngineeringLabs/arrow2-convert#108
• Update to latest arrow2 + new datatypes pola-rs/polars#8295

Fixes #1805
Fixes #1809

[teh-cmc]

Running the new extended memory_usage example:

Short EntityPath uses 78 bytes in RAM

--- 1 rows each containing 1 points (packed=false) ---
Arrow payload containing 1x Pos2 uses 2.9 kiB bytes in RAM
Arrow LogMsg containing 1x Pos2 uses 7.6 kiB-10.1 kiB bytes in RAM, and 794 B bytes encoded

--- 1 rows each containing 1 points (packed=true) ---
Arrow payload containing 1x Pos2 uses 2.5 kiB bytes in RAM
Arrow LogMsg containing 1x Pos2 uses 7.6 kiB-9.7 kiB bytes in RAM, and 746 B bytes encoded

--- 1 rows each containing 1000 points (packed=false) ---
Arrow payload containing 1000x Pos2 uses 10.3 kiB bytes in RAM
Arrow LogMsg containing 1000x Pos2 uses 15.4 kiB-17.5 kiB bytes in RAM, and 7.9 kiB bytes encoded

--- 1 rows each containing 1000 points (packed=true) ---
Arrow payload containing 1000x Pos2 uses 10.3 kiB bytes in RAM
Arrow LogMsg containing 1000x Pos2 uses 15.4 kiB-17.5 kiB bytes in RAM, and 7.8 kiB bytes encoded

--- 100000 rows each containing 1 points (packed=false) ---
Arrow payload containing 1x Pos2 uses 90.6 MiB bytes in RAM
Arrow LogMsg containing 1x Pos2 uses 4.8 MiB-95.8 MiB bytes in RAM, and 1.6 MiB bytes encoded

--- 100000 rows each containing 1 points (packed=true) ---
Arrow payload containing 1x Pos2 uses 54.0 MiB bytes in RAM
Arrow LogMsg containing 1x Pos2 uses 4.8 MiB-59.3 MiB bytes in RAM, and 1.6 MiB bytes encoded

--- 100000 rows each containing 1000 points (packed=false) ---
Arrow payload containing 1000x Pos2 uses 851 MiB bytes in RAM
Arrow LogMsg containing 1000x Pos2 uses 767 MiB-1.6 GiB bytes in RAM, and 683 MiB bytes encoded

--- 100000 rows each containing 1000 points (packed=true) ---
Arrow payload containing 1000x Pos2 uses 816 MiB bytes in RAM
Arrow LogMsg containing 1000x Pos2 uses 767 MiB-1.5 GiB bytes in RAM, and 683 MiB bytes encoded

[teh-cmc]

Closing -- will get fixed automagically by #2354