Refactor Knowledge struct into shared package

Moved the Knowledge struct and related types to the shared package, updating all references across the codebase. This improves modularity and enables better reuse of the Knowledge type across different components.

cmd/console/cmd.go

@@ -9,6 +9,7 @@ import (
 	"time"
 
 	"gitea.stevedudenhoeffer.com/steve/answer/pkg/agents"
+	"gitea.stevedudenhoeffer.com/steve/answer/pkg/agents/shared"
 
 	"gitea.stevedudenhoeffer.com/steve/answer/pkg/agents/console"
 
@@ -102,7 +103,7 @@ func main() {
 
 			c := console.Agent{
 				Model:  m,
-				OnDone: func(ctx context.Context, knowledge agents.Knowledge) error { return nil },
+				OnDone: func(ctx context.Context, knowledge shared.Knowledge) error { return nil },
 				OnCommandStart: func(ctx context.Context, command string) error {
 					slog.Info("command", "command", command)
 					return nil