refactor(games): make things consistent!

[d1rshan]

make falling words and survival consistent in code

[greptile-apps]

Greptile Summary

This PR refactors the falling-words game to match the structural conventions already established in the survival game, with no functional changes intended.

• Component files are renamed to generic names (field.tsx, hud.tsx) and exports are unified; the engine is renamed from use-falling-words-game.ts to engine.ts, and its return shape is restructured into { game, actions, wordBank } to mirror survival/engine.ts.
• The game-over overlay is extracted from Field into the shared GameOver component, useSubmitGameResult replaces the inline result-saving logic in the view, and UseGameOptions.onComplete is aligned with the survival engine's type (dropping the unused Promise<void> overload and the void keyword on the call site).
• getWordBank drops the ?? null fallback, making it consistent with the registry's Record<WordBankId, WordBank> type; survival/engine.ts also has its gameId field tightened from string to GameId.

Confidence Score: 5/5

Safe to merge — all changes are structural renames and consolidations with no behavioural differences.

The diff is a pure refactor: file renames, return-shape reorganisation, shared-component extraction, and minor type tightening. The focusedWordId logic rewrite is logically equivalent to the original. The getWordBank null-removal is correct given the registry's exhaustive Record<WordBankId, WordBank> type. No new code paths, side effects, or data mutations are introduced.

No files require special attention.

Important Files Changed

Filename	Overview
apps/frontend/src/features/content/word-banks/manager.ts	Removes the ?? null fallback; safe because the registry is typed as Record<WordBankId, WordBank> (all keys always present), so the return type is now the non-nullable WordBank.
apps/frontend/src/features/games/falling-words/engine.ts	Renamed from use-falling-words-game.ts; return value restructured into { game, actions, wordBank } to mirror survival/engine.ts; UseGameOptions type now matches survival's; void keyword removed before onComplete call (safe, callback is typed as => void).
apps/frontend/src/features/games/falling-words/view.tsx	Refactored to use the shared useSubmitGameResult hook and the new GameOver component; wordBank.label access is safe now that getWordBank returns non-nullable WordBank.
apps/frontend/src/features/games/falling-words/components/field.tsx	Renamed from falling-words-field.tsx; game-over overlay extracted into the shared GameOver component in the view, score prop removed accordingly; phase prop is still used for the idle prompt.
apps/frontend/src/features/games/survival/engine.ts	Minor change: gameId: string tightened to gameId: GameId in UseGameOptions, making the type consistent with the falling-words engine.
apps/frontend/src/features/games/survival/view.tsx	Only change is the import rename from SurvivalHud to Hud; rest of the file unchanged.
apps/frontend/src/features/games/falling-words/types.ts	Removed UseFallingWordsGameOptions and CompletedGameResult types that are now consolidated into UseGameOptions in the engine file.

_{Reviews (2): Last reviewed commit: "void" | Re-trigger Greptile}

[greptile-apps]

wordBank can be null (since getWordBank returns WordBank | null), so accessing .label directly will throw at runtime if the word bank ID isn't found. The survival view handles this correctly with an optional chain and fallback.

Suggested change

	<GameMeta wordBankLabel={wordBank.label} gameName={meta.name} />
	<GameMeta wordBankLabel={wordBank?.label ?? meta.defaultWordBankId} gameName={meta.name} />