Implemented multiple campaign support via a campaign directory registry with explicit campaign IDs

internal/config/load.go

@@ -194,7 +194,7 @@ func mergeCampaignSession(campaignCfg *CampaignConfig, sessionCfg *SessionConfig
 		return ResolvedStableInputs{}, fmt.Errorf("session config is required")
 	}
 
-	campaignName := strings.TrimSpace(campaignCfg.Campaign)
+	campaignName := CampaignID(campaignCfg)
 	sessionCampaign := strings.TrimSpace(sessionCfg.Campaign)
 	if sessionCampaign != "" && campaignName != "" && sessionCampaign != campaignName {
 		return ResolvedStableInputs{}, fmt.Errorf(
@@ -234,6 +234,14 @@ func mergeCampaignSession(campaignCfg *CampaignConfig, sessionCfg *SessionConfig
 	return stable, nil
 }
 
+// CampaignID returns the canonical campaign identity from campaign config.
+func CampaignID(cfg *CampaignConfig) string {
+	if cfg == nil {
+		return ""
+	}
+	return strings.TrimSpace(cfg.CampaignID)
+}
+
 func selectStableInput(campaignValue, sessionValue, campaignPath, sessionPath string) ResolvedInputFile {
 	if strings.TrimSpace(sessionValue) != "" {
 		return ResolvedInputFile{
@@ -316,6 +324,7 @@ func applyPipelineDefaults(cfg *PipelineConfig) {
 		return
 	}
 	applyWorkspaceDefaults(&cfg.Workspace)
+	applyCampaignsDefaults(&cfg.Campaigns)
 	applyStorageDefaults(&cfg.Storage)
 	applySpoolDefaults(&cfg.Spool)
 	applyCacheDefaults(&cfg.Cache)
@@ -331,6 +340,15 @@ func applyPipelineDefaults(cfg *PipelineConfig) {
 	applyScriptoriumDefaults(cfg.Scriptorium)
 }
 
+func applyCampaignsDefaults(cfg *CampaignsConfig) {
+	if cfg == nil {
+		return
+	}
+	if cfg.Root == "" {
+		cfg.Root = DefaultCampaignsRoot
+	}
+}
+
 func applyWorkspaceDefaults(cfg *WorkspaceConfig) {
 	if cfg == nil {
 		return