Improve convert considerations in osu!taiko

[Lawtrohux]

From the moment I had to implement it, blanket nerfing star rating of converts was something I severely disliked.

This change aims to

• Remove conditional convert nerf to starrating, and focus on what becomes abuseable - stamina.
• Harshen MonoStaminaFactor's accuracy curve, keeping the same performance points for the theoretical limits of stamina (an SS on a map like StrangeProgram)
• Nerf stamina based on the concept that with most high-end converts, finger count gets increased by 150%, thus our considerations for stamina must be nerfed by 150%, as we assume a finger count of 4.
• Disable the mono (single coloured) note buff that's found in stamina, to ensure that MonoStaminaFactor behaves correctly.
• Clean up the instances of where stamina and relax share nerfs, and implement them in line.

This will 100% need a sheet, and some absolute scrutinisation of values @ppy/taiko-pp-commitee, I'm not repeating last deploy, and I hope to catch it much sooner if there's issues to be faced.

[Lawtrohux]

@ppy/pp-maintainers could i also have a sheet here, thank you

[tsunyoku]

!diffcalc
RULESET=taiko
OSU_A=https://github.com/ppy/osu/tree/pp-dev
OSU_B=#31546

[github-actions]

Target: #31546
Spreadsheet: https://docs.google.com/spreadsheets/d/1WTDEStF2Zbh_Vh2Hm_v5DlNHWhVeB8N2-78dD7nb7o4/edit

[Lawtrohux]

I'm personally happy with the sheet, as well as the feedback I've received from convert players.

[sw1tchbl4d3r]

Looking forward to the day we can drop the isConvert flag but for now this will have to suffice.

[stanriders]

@tsunyoku you wanted to scrutinize this one extra hard iirc

[tsunyoku]

Yeah, I did - whenever I see the word "convert" then I instantly feel a need to be extra cautious. This seems okay though - can continue.