Fixes#13862
Updates the webhook OpenAPI schema to match the current API behavior for
webhook secrets and supported subscription events.
## Why
Current source already creates per-webhook secrets, returns `secret`
from the account webhook API, and uses that secret to sign outbound
webhook requests with `X-Chatwoot-Signature`.
The OpenAPI schema was behind that contract:
- `components.schemas.webhook` did not include the returned `secret`
field.
- Webhook subscription enums did not include the typing events that are
already available in the dashboard webhook form and handled by
`WebhookListener`.
## What this change does
- Documents `secret` on the webhook response schema.
- Documents the outbound webhook signing headers associated with
`secret`: `X-Chatwoot-Timestamp`, `X-Chatwoot-Signature`, and
`X-Chatwoot-Delivery`.
- Adds `conversation_typing_on` and `conversation_typing_off` to webhook
subscription enums.
- Regenerates the main and tag-group swagger JSON files.
## Validation
- Ran `bundle exec rails swagger:build`.
- Ran `bundle exec rspec spec/swagger/openapi_spec.rb`.
- Verified generated swagger JSON includes `secret`,
`conversation_typing_on`, and `conversation_typing_off` in the webhook
schemas.
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Co-authored-by: Syed Muhammad Bilal <sdmhbilal@users.noreply.github.com>
Co-authored-by: Sojan Jose <sojan@pepalo.com>
