Closes#12303
### What’s Changed
- Replace auto‐save with explicit Save / Cancel
Webhook forms now use manual “Save” and “Cancel” buttons instead of the
old debounced auto‐save/update.
- Separate “New” and “Detail” routes
Two dedicated paths `/settings/webhooks/new` for creation and
/`settings/webhooks/:webhookId` for editing, making the UX clearer.
- URL hint & normalization
If a user omits the http(s):// scheme, we display a “Will be saved as
https://…” hint and automatically default to HTTPS.
- Centralized validation with Zod
Introduced a `webhookFormSchema` for client‐side URL, operations, and
secret validation.
- Storybook coverage
Added stories for both “New Webhook” and “Webhook Detail”
- Unit tests
Added tests for the new `useWebhookForm` hook
closes#4714
We cannot set null expiration dates for api keys. So we will set to 100
years instead of null. If apiKey expires in more that 10 years, it is
displayed as "Never expires"
