feat: publish standalone worker

Separate worker packaging and service lifecycle from the control plane.

app/models/llm.go

@@ -0,0 +1,17 @@
+package models
+
+import "rsgit.ru/rsmon/rsmon/app/models/concerns"
+
+// LLM stores an OpenAI-compatible LLM endpoint available to checks.
+type LLM struct {
+	concerns.Model
+	AccountID *int64       `json:"account_id" gorm:"type:bigint REFERENCES accounts(id);index"`
+	Account   *Account     `json:"-"`
+	Name      string       `json:"name" gorm:"not null"`
+	URL       string       `json:"url" gorm:"not null"`
+	ModelName string       `json:"model" gorm:"column:model;not null"`
+	APIKey    string       `json:"-" gorm:"not null"`
+	Kind      string       `json:"kind" gorm:"not null;default:'openai'"`
+	Workers   []WorkerNode `json:"-" gorm:"many2many:worker_llms;"`
+	concerns.Timestamped
+}