One component per file; GAME OVER offers CONTINUE

PRD G1 asks for one component per file. Eight files held two or
three; their eleven extra components move to files of their own,
helpers stay where both sides use them, and an archtest now fails
any file that holds two.

PRD 4.4 and the request say an error always offers CONTINUE.
ErrorState's button read RETRY; it now reads CONTINUE, under the
CONTINUE? countdown, on the crash screen and the lost page alike.

AGENTS.md

@@ -54,7 +54,7 @@ Imports point down only. Same-tier imports are forbidden. `internal/archtest` en
 
 ## Component rules
 
-- Signatures and results: PRD §5.1, held by archtest `TestComponentsTakeTheirOptions`: `Name` takes `NameOptions` and returns `NameResult`. Zero options give the default look; required values are parameters. Sizes in options are dots.
+- Signatures and results: PRD §5.1, held by archtest `TestComponentsTakeTheirOptions`: `Name` takes `NameOptions` and returns `NameResult`, one component per file. Zero options give the default look; required values are parameters. Sizes in options are dots.
 - `k := pixel.K(c)` once per component; layout sizes through `k.D(n)`. Integer options default through `pixel.Or`.
 - Custom-drawn controls end their Draw with `g.Finish(st)`. Grids of cells moved by arrows use `pixel.Pad`; custom-drawn sliders use `input.SlideBase`; every clock runs at S5's 4–15 fps (`checkFPS` panics otherwise): a blink is `g.Step(4)%4 < 2`, a timer counts quarter seconds, and a view that changes on whole seconds asks `k.At`; one-shot timing steps with `k.Since`, which holds at zero when the clock steps back; a stored start is read through `k.Elapsed(&t)`, which moves it to now when the clock steps back; drawing from time quantizes it to whole frames (`Truncate(time.Second / 15)`); a decorative one-shot on a cue steps with `k.Shot`, which Reduce Motion spends whole; a view that changes at a known moment asks `k.At`; a two-way slide (bars, fades, wipes) steps with `k.Toward`, which turns from where it is.
 - A one-shot effect inside a lasting view starts when its cue changes (a `Cue` option read through `k.Cue`, or a value that rises), never on its first frame. A state screen (`ErrorState`, `SuccessState`) starts when it appears. Decorative motion jumps to its end under Reduce Motion; countdowns and loaders keep time.