feat: implement ntfy-discord bridge in Go

- SSE subscription to ntfy with auto-reconnect
- Discord webhook integration with embed formatting
- Priority to color mapping, tag to emoji conversion
- Native HashiCorp Vault support (Kubernetes + token auth)
- Hot reload secrets via fsnotify or Vault polling
- Prometheus metrics (/metrics endpoint)
- Health/ready endpoints for Kubernetes probes
- Comprehensive unit tests and fuzz tests
- Multi-stage Docker build (~10MB scratch image)
- CI/CD pipeline for Gitea Actions

go.mod

@@ -0,0 +1,38 @@
+module git.daviestechlabs.io/daviestechlabs/ntfy-discord
+
+go 1.25
+
+require (
+	github.com/fsnotify/fsnotify v1.7.0
+	github.com/hashicorp/vault/api v1.22.0
+	github.com/hashicorp/vault/api/auth/kubernetes v0.10.0
+	github.com/prometheus/client_golang v1.19.0
+)
+
+require (
+	github.com/beorn7/perks v1.0.1 // indirect
+	github.com/cenkalti/backoff/v4 v4.3.0 // indirect
+	github.com/cespare/xxhash/v2 v2.2.0 // indirect
+	github.com/go-jose/go-jose/v4 v4.1.1 // indirect
+	github.com/hashicorp/errwrap v1.1.0 // indirect
+	github.com/hashicorp/go-cleanhttp v0.5.2 // indirect
+	github.com/hashicorp/go-multierror v1.1.1 // indirect
+	github.com/hashicorp/go-retryablehttp v0.7.8 // indirect
+	github.com/hashicorp/go-rootcerts v1.0.2 // indirect
+	github.com/hashicorp/go-secure-stdlib/parseutil v0.2.0 // indirect
+	github.com/hashicorp/go-secure-stdlib/strutil v0.1.2 // indirect
+	github.com/hashicorp/go-sockaddr v1.0.7 // indirect
+	github.com/hashicorp/hcl v1.0.1-vault-7 // indirect
+	github.com/mitchellh/go-homedir v1.1.0 // indirect
+	github.com/mitchellh/mapstructure v1.5.0 // indirect
+	github.com/prometheus/client_model v0.5.0 // indirect
+	github.com/prometheus/common v0.48.0 // indirect
+	github.com/prometheus/procfs v0.12.0 // indirect
+	github.com/ryanuber/go-glob v1.0.0 // indirect
+	golang.org/x/crypto v0.40.0 // indirect
+	golang.org/x/net v0.42.0 // indirect
+	golang.org/x/sys v0.34.0 // indirect
+	golang.org/x/text v0.27.0 // indirect
+	golang.org/x/time v0.12.0 // indirect
+	google.golang.org/protobuf v1.32.0 // indirect
+)