Bolus initiating state + spinning border instead of the spinner

[Sjoerd-Bo3]

Summary

Restructured to build on top of the bolus-initiating feature rather than reimplement it. Two commits:

Commit 1 — Add the bolus initiating state (with a spinner)

A faithful port of the "show bolus initiating" feature:

• New BolusStatus { noBolus, initiating, inProgress }, derived from the pump's bolusState.
• DeviceDataManager.bolusTrigger now carries BolusStatus (was Bool), mapping status.bolusState → .initiating / .inProgress / (default) .noBolus.
• APSManager creates the bolus reporter for initiating+inProgress, clears it on noBolus.
• HomeStateModel and TreatmentsStateModel track bolusStatus; isBolusInProgress is replaced by bolusStatus != .noBolus.
• Home bolus card and the Treatments in-progress row show an "Initiating…" label with a ProgressView spinner (in place of the cancel button) during initiating.

Commit 2 — Show the spinning border instead of the spinner

On top of commit 1, replace that ProgressView with our reusable spinning border (the pump reservoir / loop-pill one):

• Home card: the card border spins while initiating, then switches to the determinate left→right progress fill once delivering.
• Treatments row: the card shows the spinning border while initiating; the cancel button returns once delivering.
• Both borders use a 3pt line so there's no thickness jump on the initiating → inProgress transition.

Notes

• Structured so the feature is included and then modified — if the upstream feature later lands and you sync dev, the overlap is on these same files and resolves to "keep the border, drop the spinner."
• External/manual boluses unaffected: .initiating/.inProgress come from the pump's own bolusState.
• Localization catalog entries for "Initiating…" are omitted (the String(localized:) calls fall back to the literal), consistent with how this fork has handled .xcstrings.

Verification

• Builds via the compile_check simulator workflow on this branch (only place the submodules/build can be validated).