Implement Multi-Process Handling (#7)

Refactor code to support starting of multiple back end llama.cpp servers. This functionality is exposed as `profiles` to create a simple configuration format. 

Changes: 

* refactor proxy tests to get ready for multi-process support
* update proxy/ProxyManager to support multiple processes (#7)
* Add support for Groups in configuration
* improve handling of Model alias configs
* implement multi-model swapping
* improve code clarity for swapModel
* improve docs, rename groups to profiles in config

proxy/config.go

@@ -22,26 +22,30 @@ func (m *ModelConfig) SanitizedCommand() ([]string, error) {
 }
 
 type Config struct {
-	Models             map[string]ModelConfig `yaml:"models"`
 	HealthCheckTimeout int                    `yaml:"healthCheckTimeout"`
+	Models             map[string]ModelConfig `yaml:"models"`
+	Profiles           map[string][]string    `yaml:"profiles"`
+
+	// map aliases to actual model IDs
+	aliases map[string]string
+}
+
+func (c *Config) RealModelName(search string) (string, bool) {
+	if _, found := c.Models[search]; found {
+		return search, true
+	} else if name, found := c.aliases[search]; found {
+		return name, found
+	} else {
+		return "", false
+	}
 }
 
 func (c *Config) FindConfig(modelName string) (ModelConfig, string, bool) {
-	modelConfig, found := c.Models[modelName]
-	if found {
-		return modelConfig, modelName, true
+	if realName, found := c.RealModelName(modelName); !found {
+		return ModelConfig{}, "", false
+	} else {
+		return c.Models[realName], realName, true
 	}
-
-	// Search through aliases to find the right config
-	for actual, config := range c.Models {
-		for _, alias := range config.Aliases {
-			if alias == modelName {
-				return config, actual, true
-			}
-		}
-	}
-
-	return ModelConfig{}, "", false
 }
 
 func LoadConfig(path string) (*Config, error) {
@@ -60,6 +64,14 @@ func LoadConfig(path string) (*Config, error) {
 		config.HealthCheckTimeout = 15
 	}
 
+	// Populate the aliases map
+	config.aliases = make(map[string]string)
+	for modelName, modelConfig := range config.Models {
+		for _, alias := range modelConfig.Aliases {
+			config.aliases[alias] = modelName
+		}
+	}
+
 	return &config, nil
 }