feat(grpc): add gRPC server infrastructure and schedule sync service

Add gRPC server support with configurable TLS, environment-based settings, and Wire injection. Implement schedule synchronization service with task runner integration for external course data fetching.

- Add gRPC configuration with env var overrides (APP_GRPC_ENABLED, APP_GRPC_PORT, etc.)
- Create gRPC server infrastructure with runner task management
- Implement ScheduleSyncService for course data synchronization
- Add sync endpoint to schedule handler for external system integration
- Update repository with context-aware batch delete operation
- Wire all dependencies including zap logger for structured logging

go.mod

@@ -15,6 +15,8 @@ require (
 	go.uber.org/zap v1.26.0
 	golang.org/x/crypto v0.26.0
 	golang.org/x/image v0.24.0
+	google.golang.org/grpc v1.59.0
+	google.golang.org/protobuf v1.31.0
 	gopkg.in/gomail.v2 v2.0.0-20160411212932-81ebce5c23df
 	gorm.io/driver/postgres v1.5.4
 	gorm.io/driver/sqlite v1.5.4
@@ -38,6 +40,7 @@ require (
 	github.com/go-playground/universal-translator v0.18.1 // indirect
 	github.com/go-playground/validator/v10 v10.14.0 // indirect
 	github.com/goccy/go-json v0.10.2 // indirect
+	github.com/golang/protobuf v1.5.3 // indirect
 	github.com/hashicorp/hcl v1.0.0 // indirect
 	github.com/jackc/pgpassfile v1.0.0 // indirect
 	github.com/jackc/pgservicefile v0.0.0-20221227161230-091c0ba34f0a // indirect
@@ -79,7 +82,7 @@ require (
 	golang.org/x/net v0.28.0 // indirect
 	golang.org/x/sys v0.23.0 // indirect
 	golang.org/x/text v0.22.0 // indirect
-	google.golang.org/protobuf v1.31.0 // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20231120223509-83a465c0220f // indirect
 	gopkg.in/alexcesaro/quotedprintable.v3 v3.0.0-20150716171945-2caba252f4dc // indirect
 	gopkg.in/ini.v1 v1.67.0 // indirect
 	gopkg.in/yaml.v3 v3.0.1 // indirect