Phase 3: Refactor SesWebhookController into service classes

[dkwiebe]

Summary

SesWebhookController (and the forthcoming ProcessSesWebhook Job from Phase 2) handles too many responsibilities: SNS envelope unwrapping, dual payload format parsing, synthetic message ID generation, email/recipient/event DB writes, open/click special-casing, and Sentry error capture. This makes the class hard to test in isolation and hard to extend when new SES event types are added.

Implementation

1. Create app/Services/SnsPayloadParser.php

Responsible for:

• Detecting SNS-wrapped vs. direct SES payload format
• Unwrapping the SNS Message JSON string
• Computing the synthetic MD5 MessageId for direct-format events
• Returning a normalized canonical struct consumed by the processor

class SnsPayloadParser
{
    public function parse(array $raw): ParsedSesPayload  // throws on unknown format
}

2. Create app/Services/SesEventProcessor.php

Responsible for:

• firstOrCreate logic for Email, EmailRecipient, RecipientEvent
• The SES_EVENT_TYPE_TO_ENUM mapping
• Open/click recipient assignment logic
• Bounce/complaint/delivery-delay recipient extraction

class SesEventProcessor
{
    public function process(Project $project, ParsedSesPayload $payload): void
}

3. Slim down SesWebhookController / ProcessSesWebhook

Inject both services; reduce the controller/job body to:

$parsed = $this->parser->parse($rawPayload);
$this->processor->process($project, $parsed);

Acceptance Criteria

• SnsPayloadParser has unit tests for both payload formats and error paths
• SesEventProcessor has unit tests per event type (can reuse data from existing feature tests)
• All existing webhook feature tests continue to pass
• Controller/Job body is under ~30 lines of logic