Simplify ad response shape

[jahooma]

Summary

Simplifies the ad provider contract so Gravity and Carbon always return an ads array instead of a banner-or-choice union.
Updates the CLI ad hook, chat, and waiting room render paths to consume that array directly while preserving the choice banner behavior.
Normalizes no-fill and error responses from the ads API to the same array-based shape.

Validation

• bun run typecheck in cli
• bun run typecheck in web

[greptile-apps]

Greptile Summary

This PR successfully simplifies the ad provider contract by replacing the banner | choice variant union with a uniform { ads: NormalizedAd[] } shape across all providers, the API route, and the CLI hook. The A/B variant assignment logic (getGravityVariant) and the separate banner cache are removed, and both render call sites are cleaned up to consume ads directly.

Confidence Score: 5/5

Safe to merge; all remaining findings are minor style suggestions.

No logic bugs or data-integrity issues found. The simplification is correct end-to-end: client, server, and provider types all agree on the new array shape. The two P2 comments are optional follow-ups.

No files require special attention.

Important Files Changed

Filename	Overview
web/src/lib/ad-providers/types.ts	Removed AdVariant type and simplified FetchAdResult from a banner/choice union to a plain { ads: NormalizedAd[] }
web/src/lib/ad-providers/gravity.ts	Removed A/B variant logic (getGravityVariant, BANNER_PLACEMENT_ID) and now always returns { ads: [...] }; straightforward simplification.
web/src/lib/ad-providers/carbon.ts	Trivially updated return value from { variant: 'choice', ads } to { ads }; no logic change.
web/src/app/api/v1/ads/_post.ts	Added noAdsResponse helper and unified all response paths to { ads, variant: 'choice', provider }; variant field is vestigial but harmless.
cli/src/hooks/use-gravity-ad.ts	Removed AdData/AdVariant types, banner cache, and showAd(); now uses a single ads state and choice cache path; showChoiceAds is now a trivial wrapper around setAds.
cli/src/chat.tsx	Switched from adData with variant-conditional array construction to ads directly; render logic is cleaner.
cli/src/components/waiting-room-screen.tsx	Same adData → ads simplification as chat.tsx; no issues.

Prompt To Fix All With AI

This is a comment left during a code review.
Path: cli/src/hooks/use-gravity-ad.ts
Line: 183-186

Comment:
**`showChoiceAds` is now a trivial wrapper**

After removing `showAd`, `showChoiceAds` is a single-line function wrapping `setAds`. It could be inlined at its two call sites to further reduce indirection.

Then replace the two `showChoiceAds(result.ads)` / `showChoiceAds(cachedSet)` calls with `setAds(result.ads)` / `setAds(cachedSet)` directly.

**Context Used:** Find ways to simplify the implementation ([source](https://app.greptile.com/review/custom-context?memory=instruction-0))

How can I resolve this? If you propose a fix, please make it concise.

---

This is a comment left during a code review.
Path: web/src/app/api/v1/ads/_post.ts
Line: 56-61

Comment:
**Vestigial `variant` field in responses**

Now that both the CLI hook and the server-side type contract have dropped the banner/choice distinction, `variant: 'choice'` in `noAdsResponse` (and in the success/error responses in `_post.ts`) is never read by any consumer. Dropping it would complete the simplification and keep the wire format consistent with the new `FetchAdResult` shape.

```suggestion
function noAdsResponse(provider: AdProviderId) {
  return NextResponse.json(
    { ads: [], provider },
    { status: 200 },
  )
}
```

**Context Used:** Find ways to simplify the implementation ([source](https://app.greptile.com/review/custom-context?memory=instruction-0))

How can I resolve this? If you propose a fix, please make it concise.

_{Reviews (1): Last reviewed commit: "Simplify ad response shape" | Re-trigger Greptile}

[greptile-apps]

showChoiceAds is now a trivial wrapper

After removing showAd, showChoiceAds is a single-line function wrapping setAds. It could be inlined at its two call sites to further reduce indirection.

Then replace the two showChoiceAds(result.ads) / showChoiceAds(cachedSet) calls with setAds(result.ads) / setAds(cachedSet) directly.

Context Used: Find ways to simplify the implementation (source)

Prompt To Fix With AI

This is a comment left during a code review.
Path: cli/src/hooks/use-gravity-ad.ts
Line: 183-186

Comment:
**`showChoiceAds` is now a trivial wrapper**

After removing `showAd`, `showChoiceAds` is a single-line function wrapping `setAds`. It could be inlined at its two call sites to further reduce indirection.

Then replace the two `showChoiceAds(result.ads)` / `showChoiceAds(cachedSet)` calls with `setAds(result.ads)` / `setAds(cachedSet)` directly.

**Context Used:** Find ways to simplify the implementation ([source](https://app.greptile.com/review/custom-context?memory=instruction-0))

How can I resolve this? If you propose a fix, please make it concise.

Note: If this suggestion doesn't match your team's coding style, reply to this and let me know. I'll remember it for next time!

[greptile-apps]

Vestigial variant field in responses

Now that both the CLI hook and the server-side type contract have dropped the banner/choice distinction, variant: 'choice' in noAdsResponse (and in the success/error responses in _post.ts) is never read by any consumer. Dropping it would complete the simplification and keep the wire format consistent with the new FetchAdResult shape.

Suggested change

	function noAdsResponse(provider: AdProviderId) {
	return NextResponse.json(
	{ ads: [], variant: 'choice', provider },
	{ status: 200 },
	)
	}
	function noAdsResponse(provider: AdProviderId) {
	return NextResponse.json(
	{ ads: [], provider },
	{ status: 200 },
	)
	}

Context Used: Find ways to simplify the implementation (source)

Prompt To Fix With AI

This is a comment left during a code review.
Path: web/src/app/api/v1/ads/_post.ts
Line: 56-61

Comment:
**Vestigial `variant` field in responses**

Now that both the CLI hook and the server-side type contract have dropped the banner/choice distinction, `variant: 'choice'` in `noAdsResponse` (and in the success/error responses in `_post.ts`) is never read by any consumer. Dropping it would complete the simplification and keep the wire format consistent with the new `FetchAdResult` shape.

```suggestion
function noAdsResponse(provider: AdProviderId) {
  return NextResponse.json(
    { ads: [], provider },
    { status: 200 },
  )
}
```

**Context Used:** Find ways to simplify the implementation ([source](https://app.greptile.com/review/custom-context?memory=instruction-0))

How can I resolve this? If you propose a fix, please make it concise.