Exposing subsystem functionality controls in `conf.toml`

[goodboy]

Obviously related to both #529 and #221 we have a TON of stuff in many sub-systems that can be exposed for manual user control 😂

The latest example of this is from #523 which more or less allows user tweaking of the "scaling" of all widgets in our UIs by setting a font size..

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Where to start

• search for todo notes in the code base with:

  • git grep config.toml
  • git grep conf.toml

• more or less off the top of my head (lul):

  • .data.feed. throttling controls (search for tick_throttle)
  • data.flows.Flume memory allocation size depending on OHLC sample rate
  • .service related (actor) daemon socket-address settings, maybe registry definitions?
    • for eg. defining the network transport layer addresses over multiple hosts 😎
  • .accounting._allocate settings for order sizing and limits
    • (maybe on a per asset type basis?)

Testing

• add at least one validation test that ensures the minimal set
  of fields are present in the conf.toml file
• ideally per subsystem functionality tests of some sort:
  • setting .data.feed throttle rate results in measurably
    limited tick rates.
  • set .data.history related ShmArray (buffer) mem size
    and make sure /dev/shm files are sized to match.