feat: support web calls in webhook

[cubic-dev-local]

## What does this PR do?

Mandatory Tasks (DO NOT REMOVE)

• I have self-reviewed the code (A decent size PR without self-review might be rejected).
• N/A I have updated the developer docs in /docs if this PR makes changes that would require a documentation change. If N/A, write N/A here and check the checkbox.
• I confirm automated tests are in place that prove my fix is effective or that my feature works.

How should this be tested?

---

Based on: calcom/cal.com#23788

---

Summary by cubic

Adds web call support to the Retell webhook. Credits are now charged for web calls by resolving agent_id to the owning user or team when phone data is missing.

• New Features
  • Accepts web calls: phone fields and direction are optional; detected via call_type=web_call or missing from_number.
  • Resolves agent_id via PrismaAgentRepository to charge the correct user or team.
  • Extracts credit charging into chargeCreditsForCall; uses rate-per-minute env var and rounds up credits.
  • Inbound-call skip now applies only to phone calls; logging improved.
  • Adds unit tests for web call paths (agent found, team agent, missing agent_id, agent not found).

[cubic-dev-ai]

1 issue found across 2 files

Prompt for AI agents (all 1 issues)

Understand the root cause of the following 1 issues and fix them.


<file name="apps/web/app/api/webhooks/retell-ai/route.ts">

<violation number="1" location="apps/web/app/api/webhooks/retell-ai/route.ts:141">
This change introduces two different sources of truth for determining who to bill for a call: `from_number` for phone calls and `agent_id` for web calls. This fragments the billing logic across two different data models and repositories. A more robust architecture would unify this, for example by assigning a consistent billing entity when a call is initiated, rather than deriving it from different properties after the call has ended.

        DEV MODE: This violation would have been filtered out by GPT-5.
Reasoning:
• **GPT-5**: Intentional per-call-type lookup (agent_id for web calls, from_number for phone calls) that both resolve to the same billing owner (userId/teamId) and feed a unified chargeCreditsForCall. No conflicting rules introduced; this is an architectural choice without clear negative impact.</violation>
</file>

_{React with 👍 or 👎 to teach cubic. Mention @cubic-dev-ai to give feedback, ask questions, or re-run the review.}

[cubic-dev-ai]

This change introduces two different sources of truth for determining who to bill for a call: from_number for phone calls and agent_id for web calls. This fragments the billing logic across two different data models and repositories. A more robust architecture would unify this, for example by assigning a consistent billing entity when a call is initiated, rather than deriving it from different properties after the call has ended.

    DEV MODE: This violation would have been filtered out by GPT-5.

Reasoning:
• GPT-5: Intentional per-call-type lookup (agent_id for web calls, from_number for phone calls) that both resolve to the same billing owner (userId/teamId) and feed a unified chargeCreditsForCall. No conflicting rules introduced; this is an architectural choice without clear negative impact.

Prompt for AI agents

Address the following comment on apps/web/app/api/webhooks/retell-ai/route.ts at line 141:

<comment>This change introduces two different sources of truth for determining who to bill for a call: `from_number` for phone calls and `agent_id` for web calls. This fragments the billing logic across two different data models and repositories. A more robust architecture would unify this, for example by assigning a consistent billing entity when a call is initiated, rather than deriving it from different properties after the call has ended.

        DEV MODE: This violation would have been filtered out by GPT-5.
Reasoning:
• **GPT-5**: Intentional per-call-type lookup (agent_id for web calls, from_number for phone calls) that both resolve to the same billing owner (userId/teamId) and feed a unified chargeCreditsForCall. No conflicting rules introduced; this is an architectural choice without clear negative impact.</comment>

<file context>
@@ -124,15 +117,74 @@ async function handleCallAnalyzed(callData: any) {
+  let teamId: number | undefined;
+
+  // Handle web calls vs phone calls
+  if (call_type === &quot;web_call&quot; || !from_number) {
+    if (!agent_id) {
+      log.error(`Web call ${call_id} missing agent_id, cannot charge credits`);
</file context>

[internal] Confidence score: 8/10

[internal] Posted by: System Design Agent

[github-actions]

This PR is being marked as stale due to inactivity.