Round to supported rate before setting temp basal rate

[MikePlante1]

The issue this addresses would not be noticed with Loop, as Loop rounds before attempting to enact a temporary basal rate. This issue became apparent when using Trio, though, since Trio does not round before attempting to enact a temporary basal rate, leaving the task of rounding up to the pump's submodule. OmniBLE and OmniKit both already internally handle this rounding task, so this PR aims to add it to MinimedKit as well.

[MikePlante1]

I added this commit to my in-vitro build of Trio-dev.

I added a debugging log message in Trio whenever it attempts to enact a temp basal rate that is unsupported by the pump. Before when this was triggered, I would check Trio's History and see two temp basal records for the same time and one of them would be for the unsupported rate. Here's an example of that:

Since adding this commit to my in-vitro Trio build, however, I have had a couple log messages for attempts to enact an unsupported basal rate, but Trio's History only shows the single rounded and supported temp basal rate. Given this, I think this commit solves this issue.

[marionbarker]

Status

Changes look good.

Code Review

The code changes look appropriate and necessary for an app that relies on the pump manager to manage allowed pump basal rates.

Test

• Loop test, below, was successful
• Trio test, previous comment, was successful

Loop tests

Loop will not call with a rate that is not "allowed". So this test is to just ensure Loop continues to work as expected with the modification.

Configuration

• LoopWorkspace dev branch, commit 3d48a5c
• Use MinimedKit version from this PR, commit 1b7168b
• Build on to SE 2nd gen phone running iOS 18.4
• Add MDT 515 pump to Loop

Test Scenario

• Set Dosing Strategy to Temp Basal only
  • Change the glucose source which caused an abrupt drop in glucose, so initially Loop lowered TB
  • Configure glucose trace to be flat and add carbs but do not bolus
• As Loop commands a change to TB for MDT, report rates on Loop display and pump in table below
  • first indication was when scheduled basal was running

Loop MDT display	Basal Type	MDT pump display
1.45	Sch	1.45
0.45	TB	0.45
1.45	Sch	1.45
6.00	TB	6.0

Loop continues to work as expected. (maxBasal setting in therapy is 6 U/hr)

Trio tests

I did not reproduce the error or resolution for Trio because @MikePlante1 already did that in the previous comment.

[marionbarker]

Approving from code review and test.

[ps2]

The responsibility should be for the caller to send the right rates.

1. For automated dosing, it is important that the algo is making the right decision for rounding (up or down).
2. For manual dosing, it's important that the user know what rate they are setting.