feat: ToStringOut() for series

[DaveSkender]

Description

This is a quirky helper utility to convert ISeries (quotes and results lists) to a fixed width, CSV, or JSON string. Mostly, I'm thinking this is helpful anyone debugging or wanting to output something to Console for quick visual inspections or general development sharing. Default is OutType.FixedWidth, since I mostly had Console output and .NET Fiddle use in mind.

   i  Timestamp      Open     High      Low    Close     Volume
---------------------------------------------------------------
   1  2017-01-03   212.71  213.350  211.520  212.570   96708880
   2  2017-01-04   212.64  214.220  212.638  213.648   83348752
   3  2017-01-05   213.14  214.060  213.020  213.685   82961968
   4  2017-01-06   213.41  215.170  213.414  214.318   75744152
   5  2017-01-09   213.87  214.530  213.866  214.193   49684316
   6  2017-01-10   214.03  214.890  213.520  214.083   67500792

To do

• depends on merge of feat: Full chain streaming prototypes #1092, since it restructures IResult to be parameterless
• question: isn't there a built-in set of converters that might work better here? seems like we're re-engineering something that probably already exists in C# features.
• question: any way to use inner override of result class ToString()? Probably not. Maybe we just use .ToStringList() or .ToStringOut()
• fix: order date as first property, it's inherited, so it is always at the end right now
• fix: use of unused arguments for certain OutType values
• fix: formatting issues for date. For OutType.FixedWidth, it would ideally be the smallest format possible, keeping in mind that bars could be high frequency date/time values or wider.
• consider overload .ToString(int limitQty) or .ToString(int startIndex, int endIndex)
• add separate backlog items if some classes might have their own (property, type, value, description (from XML docs)), ref:

  Property   Type          Value  Description
  -------------------------------------------------------------------
  Timestamp  DateTime 2024-02-02  The close date/time for this period
  Size       Decimal        3.00  High - Low price
  Body       Decimal        1.00  | Open - Close | (absolute value)
  UpperWick  Decimal        1.00  High - max(Open, Close)
  ...

• fix: overall performance, needs major refactoring
• add real unit tests

[DaveSkender]

Note: overriding ToString() doesn't work on enumerable, but does work for base types.

Copilot reviewed 3 out of 3 changed files in this pull request and generated no suggestions.

Comments skipped due to low confidence (4)

tests/indicators/_common/Results/Result.Utilities.ToStringOut.Tests.cs:12

• The test method 'ToStringFixedWidth' is not implemented correctly and needs to be properly implemented.

Assert.Fail("Test not implemented, very wrong syntax.");

tests/indicators/_common/Results/Result.Utilities.ToStringOut.Tests.cs:26

• The test method 'ToStringCSV' is not implemented correctly and needs to be properly implemented.

Assert.Fail("Test not implemented, very wrong syntax.");

tests/indicators/_common/Results/Result.Utilities.ToStringOut.Tests.cs:36

• The test method 'ToStringJson' is not implemented correctly and needs to be properly implemented.

Assert.Fail("Test not implemented, very wrong syntax.");

src/_common/Generics/StringOut.cs:66

• The message should be 'ToStringOut() for JSON output ignores the number format N{decimalsToDisplay}.'

string message = $"ToStringOut() for JSON output ignores number format N{decimalsToDisplay}.";