feat(epic1): implement core infrastructure (stories 1.1-1.5)

Implemented Epic 1 core kernel and infrastructure stories:

Story 1.1: Enhanced DI Container
- Added providers for database, health, metrics, and error bus
- Extended CoreModule to include all core services

Story 1.2: Database Layer with Ent ORM
- Created Ent schema for User, Role, Permission, AuditLog entities
- Implemented many-to-many relationships (User-Role, Role-Permission)
- Created database client wrapper with connection pooling
- Added database provider to DI container with migration support

Story 1.3: Health Monitoring and Metrics System
- Implemented health check registry and interface
- Added database health checker
- Created Prometheus metrics system with HTTP instrumentation
- Added health and metrics providers to DI container

Story 1.4: Error Handling and Error Bus
- Implemented channel-based error bus
- Created ErrorPublisher interface
- Added error bus provider with lifecycle management

Story 1.5: HTTP Server Foundation
- Created HTTP server with Gin framework
- Implemented comprehensive middleware stack:
  - Request ID generation
  - Structured logging
  - Panic recovery with error bus integration
  - Prometheus metrics collection
  - CORS support
- Registered core routes: /healthz, /ready, /metrics
- Integrated with FX lifecycle for graceful shutdown

All components are integrated via DI container and ready for use.

internal/ent/runtime.go

@@ -0,0 +1,73 @@
+// Code generated by ent, DO NOT EDIT.
+
+package ent
+
+import (
+	"time"
+
+	"git.dcentral.systems/toolz/goplt/internal/ent/auditlog"
+	"git.dcentral.systems/toolz/goplt/internal/ent/permission"
+	"git.dcentral.systems/toolz/goplt/internal/ent/role"
+	"git.dcentral.systems/toolz/goplt/internal/ent/schema"
+	"git.dcentral.systems/toolz/goplt/internal/ent/user"
+)
+
+// The init function reads all schema descriptors with runtime code
+// (default values, validators, hooks and policies) and stitches it
+// to their package variables.
+func init() {
+	auditlogFields := schema.AuditLog{}.Fields()
+	_ = auditlogFields
+	// auditlogDescActorID is the schema descriptor for actor_id field.
+	auditlogDescActorID := auditlogFields[1].Descriptor()
+	// auditlog.ActorIDValidator is a validator for the "actor_id" field. It is called by the builders before save.
+	auditlog.ActorIDValidator = auditlogDescActorID.Validators[0].(func(string) error)
+	// auditlogDescAction is the schema descriptor for action field.
+	auditlogDescAction := auditlogFields[2].Descriptor()
+	// auditlog.ActionValidator is a validator for the "action" field. It is called by the builders before save.
+	auditlog.ActionValidator = auditlogDescAction.Validators[0].(func(string) error)
+	// auditlogDescTimestamp is the schema descriptor for timestamp field.
+	auditlogDescTimestamp := auditlogFields[5].Descriptor()
+	// auditlog.DefaultTimestamp holds the default value on creation for the timestamp field.
+	auditlog.DefaultTimestamp = auditlogDescTimestamp.Default.(func() time.Time)
+	permissionFields := schema.Permission{}.Fields()
+	_ = permissionFields
+	// permissionDescName is the schema descriptor for name field.
+	permissionDescName := permissionFields[1].Descriptor()
+	// permission.NameValidator is a validator for the "name" field. It is called by the builders before save.
+	permission.NameValidator = permissionDescName.Validators[0].(func(string) error)
+	roleFields := schema.Role{}.Fields()
+	_ = roleFields
+	// roleDescName is the schema descriptor for name field.
+	roleDescName := roleFields[1].Descriptor()
+	// role.NameValidator is a validator for the "name" field. It is called by the builders before save.
+	role.NameValidator = roleDescName.Validators[0].(func(string) error)
+	// roleDescCreatedAt is the schema descriptor for created_at field.
+	roleDescCreatedAt := roleFields[3].Descriptor()
+	// role.DefaultCreatedAt holds the default value on creation for the created_at field.
+	role.DefaultCreatedAt = roleDescCreatedAt.Default.(func() time.Time)
+	userFields := schema.User{}.Fields()
+	_ = userFields
+	// userDescEmail is the schema descriptor for email field.
+	userDescEmail := userFields[1].Descriptor()
+	// user.EmailValidator is a validator for the "email" field. It is called by the builders before save.
+	user.EmailValidator = userDescEmail.Validators[0].(func(string) error)
+	// userDescPasswordHash is the schema descriptor for password_hash field.
+	userDescPasswordHash := userFields[2].Descriptor()
+	// user.PasswordHashValidator is a validator for the "password_hash" field. It is called by the builders before save.
+	user.PasswordHashValidator = userDescPasswordHash.Validators[0].(func(string) error)
+	// userDescVerified is the schema descriptor for verified field.
+	userDescVerified := userFields[3].Descriptor()
+	// user.DefaultVerified holds the default value on creation for the verified field.
+	user.DefaultVerified = userDescVerified.Default.(bool)
+	// userDescCreatedAt is the schema descriptor for created_at field.
+	userDescCreatedAt := userFields[4].Descriptor()
+	// user.DefaultCreatedAt holds the default value on creation for the created_at field.
+	user.DefaultCreatedAt = userDescCreatedAt.Default.(func() time.Time)
+	// userDescUpdatedAt is the schema descriptor for updated_at field.
+	userDescUpdatedAt := userFields[5].Descriptor()
+	// user.DefaultUpdatedAt holds the default value on creation for the updated_at field.
+	user.DefaultUpdatedAt = userDescUpdatedAt.Default.(func() time.Time)
+	// user.UpdateDefaultUpdatedAt holds the default value on update for the updated_at field.
+	user.UpdateDefaultUpdatedAt = userDescUpdatedAt.UpdateDefault.(func() time.Time)
+}