Adds the right-anchored game-identifier piece of the replay-overlay
mockup (docs/ui-mockups/replay-overlay-mobile.html), adapted to live
under the existing "▌ replay" headline rather than as a separate
top-bar surface — the screen-takeover redesign is intentionally
deferred per the SESSION_HANDOFF punch list.
The caption reads `GAME #{year}-{ordinal:03}` (e.g. `GAME #2026-122`
for a replay recorded 2026-05-02), matching the mockup's
`GAME #2024-127` motif. Year + chrono ordinal gives a compact,
monotonically-increasing identifier that's grep-friendly across
replay files. TYPE_CAPTION (11 px) / TEXT_SECONDARY paint so the
caption reads as subordinate metadata, not a callout.
Implementation: new ReplayOverlayGameCaption marker, new pure
helper `format_game_caption(state) -> Option<String>` (None for
Inactive / Completed since the replay is consumed in those branches),
left-side label spawn restructured into a column container holding
the headline + caption with a 2 px row gap. BANNER_HEIGHT bumped
48 → 60 px so the column fits without overflow (16 px vertical
padding + 1 px scrub + ~39 px content; +12 px banner mass is the
deliberate cost of the new content).
Two new tests (1180 → 1182): format_game_caption_covers_state_corners
pins the three branches (Inactive / Completed / Playing) plus the
zero-pad-to-3-digits invariant for early-January ordinals; and
overlay_game_caption_shows_replay_date drives ReplayPlaybackState
end-to-end and asserts the caption text on spawn and that the
overlay stays spawned through Playing → Completed.
MOVE chip restyle from the same mockup is the next commit.
funman300
54005d5494