Include high and low values in TIR in Statistics

[MikePlante1]

This changes the statistics to include the high and low values in the normal range instead of the high and low ranges. This would match the colors of the glucose dots on the Statistics screen.

For this example in a simulator, I kept high/low to the default 70/180 and manually entered these values:

Before this PR (standing)	Before this PR (laying)
After this PR (standing)	After this PR (laying)

[bjornoleh]

Code review:

The code changes looks good and are limited to the required changes for the scope of this PR.

Test build to iPhone 13 mini:

Builds: ✅
TIR definition ok both for standing and laying chart ✅
mmol/L tested ok: ✅

• 3,8 below range
• 3,9 within range
• 10,0 within range
• 10,1 above range

No uncommitted auto linting: ✅

[AndreasStokholm]

Tested in sim and on a test phone with a Pi sim. Works and shows values as expected in both mg/dL and mmol/L.

Also, big plus for removing the ligatures 👏

[bjornoleh]

Merging with two 👍