feat(server): add support for extra maps in adapter configuration

* Introduced ExtraMapConfig to allow multiple adapter configurations.
* Updated server and handler to utilize extra maps for routing.
* Added dashboard handler for metrics visualization.

cmd/vecna/convert.go

@@ -10,6 +10,7 @@ import (
 
 	"github.com/Warky-Devs/vecna.git/pkg/adapter"
 	"github.com/Warky-Devs/vecna.git/pkg/config"
+	"github.com/Warky-Devs/vecna.git/pkg/server"
 )
 
 var (
@@ -94,7 +95,37 @@ func openWriter(path string) (io.Writer, error) {
 
 // buildAdapter constructs the Adapter from the loaded config.
 func buildAdapter(cfg *config.Config) (adapter.Adapter, error) {
-	ac := cfg.Adapter
+	return buildAdapterFromConfig(cfg.Adapter)
+}
+
+// buildExtraMapAdapters builds a server.ExtraMap for each entry in cfg.ExtraMaps.
+// Unset adapter fields fall back to the global Adapter values.
+func buildExtraMapAdapters(cfg *config.Config) (map[string]server.ExtraMap, error) {
+	result := make(map[string]server.ExtraMap, len(cfg.ExtraMaps))
+	for name, mc := range cfg.ExtraMaps {
+		ac := config.AdapterConfig{
+			Type:         coalesce(mc.Type, cfg.Adapter.Type),
+			SourceDim:    coalescei(mc.SourceDim, cfg.Adapter.SourceDim),
+			TargetDim:    mc.TargetDim,
+			TruncateMode: coalesce(mc.TruncateMode, cfg.Adapter.TruncateMode),
+			PadMode:      coalesce(mc.PadMode, cfg.Adapter.PadMode),
+			Seed:         coalescei64(mc.Seed, cfg.Adapter.Seed),
+			MatrixFile:   coalesce(mc.MatrixFile, cfg.Adapter.MatrixFile),
+		}
+		adp, err := buildAdapterFromConfig(ac)
+		if err != nil {
+			return nil, fmt.Errorf("extra_map %q: %w", name, err)
+		}
+		result[name] = server.ExtraMap{
+			Adapter:       adp,
+			ForwardTarget: mc.ForwardTarget,
+		}
+	}
+	return result, nil
+}
+
+// buildAdapterFromConfig constructs an Adapter from an AdapterConfig.
+func buildAdapterFromConfig(ac config.AdapterConfig) (adapter.Adapter, error) {
 	if ac.SourceDim == 0 && ac.TargetDim == 0 {
 		return adapter.NewPassthrough(), nil
 	}
@@ -124,6 +155,27 @@ func buildAdapter(cfg *config.Config) (adapter.Adapter, error) {
 	}
 }
 
+func coalesce(a, b string) string {
+	if a != "" {
+		return a
+	}
+	return b
+}
+
+func coalescei(a, b int) int {
+	if a != 0 {
+		return a
+	}
+	return b
+}
+
+func coalescei64(a, b int64) int64 {
+	if a != 0 {
+		return a
+	}
+	return b
+}
+
 func parseTruncateModes(truncMode, padMode string) (adapter.TruncateMode, adapter.PadMode, error) {
 	var tm adapter.TruncateMode
 	switch truncMode {

cmd/vecna/serve.go

@@ -48,6 +48,11 @@ func runServe(cmd *cobra.Command, _ []string) error {
 		return fmt.Errorf("build adapter: %w", err)
 	}
 
+	extraMaps, err := buildExtraMapAdapters(cfg)
+	if err != nil {
+		return fmt.Errorf("build extra_maps: %w", err)
+	}
+
 	clients, err := buildClients(cfg)
 	if err != nil {
 		return fmt.Errorf("build clients: %w", err)
@@ -58,7 +63,7 @@ func runServe(cmd *cobra.Command, _ []string) error {
 		reg = metrics.New()
 	}
 
-	router, err := server.New(cfg, clients, adp, reg, logger)
+	router, err := server.New(cfg, clients, adp, extraMaps, reg, logger)
 	if err != nil {
 		return fmt.Errorf("build router: %w", err)
 	}