feat: richer Webhooks tab — create, toggle, delete subscriptions (#454)
* feat: richer Webhooks tab — create, toggle, delete subscriptions
Adds full webhook subscription management matching the dashboard UI:
- Create subscription dialog (name, description, events, deliver, secret)
- Per-subscription enable/disable toggle via PUT endpoint
- Delete with confirmation dialog
- Enhanced subscription cards: description, event chips, delivery badge,
secret indicator, URL display
- Search filtering across name, description, and events
- Updated Webhook.kt model with full API shape
- New HermesApiService endpoints for CRUD operations
Closes #447
* fix: remove double top padding on webhooks screen LazyColumn
* fix: use string resources in webhooks screen (sweep hardcoded strings)
* fix: resolve unresolved merge conflict in AchievementsScreen
Leftover <<<<<<< markers from a main merge broke compilation on the
webhooks-full-parity branch, cascading through ktlint/lint/tests.
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Co-authored-by: M57 <hy4ri@users.noreply.github.com>
