feat(train): a weight vest among the equipment (ADR 0034, D7)

A vest keeps its weight and, if adjustable, how far it goes. At a place
that has one, a set of bodyweight work offers it beside the weight, a
tap writing its weight in.

Whats-New: Add a weight vest to your equipment, and put its weight on a bodyweight set with a tap.
Whats-New-De: Trage eine Gewichtsweste bei deiner Ausrüstung ein und übernimm ihr Gewicht mit einem Tipp in einen Satz mit Körpergewicht.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Signed-off-by: Tizian 「ティツィアーン」 <raisondetredev@pm.me>

docs/adr/0034-train-equipment-and-plate-maths.md

@@ -76,6 +76,14 @@ No model holds an exercise, a set, a repetition or a weight.
    place: a target, the bar or handle, the plates per side, and for several targets the
    moves between them.
 
+7. **A weight vest is a kind of its own** (the developer's, 5 Nov 2026; the details the
+   agent's): `weightVest`, its weight and, for an adjustable one, how far it goes
+   (`gramsUpTo`, added to the payload without a new schema: an older app leaves the
+   kind out). What the body lifts takes weight as typed, so a vest at the place chosen
+   shows as a chip by a set's weight (`VestChip`), tapped writing its weight, an
+   adjustable one's lightest; a plan doesn't plan with it. A hand grip trainer stays
+   the person's own, by name, as it would serve one exercise, itself their own.
+
 ## Consequences
 
 - Strength plans (exercises, sets, repetitions, weights, rest) are the next step: a plan