Add config validation and dashboard

Add YAML config loading with validation, env overrides for secrets, and
a web dashboard exposing health, stats, and recent events.

gitea_test.v

@@ -0,0 +1,37 @@
+module main
+
+import sources
+
+fn test_transform_gitea_push() {
+	raw := '{"repository":{"full_name":"bruno/flowdeck"},"pusher":{"username":"bruno"},"commits":[{"message":"Fix bug","id":"a3f2c1d1234567890"}]}'
+	src := sources.GiteaSource{
+		name:         'FlowDeck'
+		webhook_path: '/webhooks/gitea-flowdeck'
+		topic:        'dev-notifs'
+		priority_map: {
+			'push': 2
+		}
+	}
+	event := sources.transform_gitea(raw, src) or { panic(err) }
+	assert event.source == 'gitea'
+	assert event.topic == 'dev-notifs'
+	assert event.priority == 2
+	assert event.message.contains('bruno/flowdeck')
+	assert event.message.contains('bruno')
+	assert event.message.contains('Fix bug')
+}
+
+fn test_transform_gitea_pull_request() {
+	raw := '{"repository":{"full_name":"bruno/flowdeck"},"action":"opened","pull_request":{"title":"New feature","merge_commit_sha":"abc123"}}'
+	src := sources.GiteaSource{
+		name:         'FlowDeck'
+		webhook_path: '/webhooks/gitea-flowdeck'
+		topic:        'dev-notifs'
+		priority_map: {
+			'pull_request': 4
+		}
+	}
+	event := sources.transform_gitea(raw, src) or { panic(err) }
+	assert event.priority == 4
+	assert event.message.contains('New feature')
+}