feat: NoMemory/Cleaner memory system + doc update

- _sdk_local/ removed (moved to standalone sdk repo)
- internal/agent/core: NoMemory/Cleaner data-flow breakpoints
- internal/memory: clean_text, document store refactor
- internal/plugin/registry.go: plugin API alignment
- docs: PLUGIN_DEV.md, ARCHITECTURE.md NoMemory/Cleaner docs
- plan.md, review.md: status update

internal/agent/core/context_test.go

@@ -6,7 +6,6 @@ import (
 	"time"
 
 	"gitcode.com/JianFeeeee/HomeAgent/internal/memory"
-	sdk "gitcode.com/JianFeeeee/HomeAgent/internal/sdk"
 )
 
 func newTestCtx() *RelevanceContext {
@@ -238,40 +237,6 @@ func containsStr(s, substr string) bool {
 	return false
 }
 
-func TestHasNoMemoryTool(t *testing.T) {
-	host := NewStageHost()
-	host.RegisterTool("no_mem_tool", sdk.ToolDef{Name: "no_mem_tool", NoMemory: true}, nil)
-	host.RegisterTool("mem_tool", sdk.ToolDef{Name: "mem_tool"}, nil)
-	lookup := host.ToolDef
-
-	gotNil := hasNoMemoryTool([]string{"no_mem_tool"}, nil)
-	if gotNil {
-		t.Error("hasNoMemoryTool with nil lookup should return false")
-	}
-
-	tests := []struct {
-		name      string
-		toolsUsed []string
-		want      bool
-	}{
-		{"empty tools", nil, false},
-		{"no matching tool", []string{"unknown"}, false},
-		{"tool without NoMemory", []string{"mem_tool"}, false},
-		{"tool with NoMemory", []string{"no_mem_tool"}, true},
-		{"mixed tools, first is no_memory", []string{"no_mem_tool", "mem_tool"}, true},
-		{"mixed tools, last is no_memory", []string{"mem_tool", "no_mem_tool"}, true},
-	}
-
-	for _, tt := range tests {
-		t.Run(tt.name, func(t *testing.T) {
-			got := hasNoMemoryTool(tt.toolsUsed, lookup)
-			if got != tt.want {
-				t.Errorf("hasNoMemoryTool(%v) = %v, want %v", tt.toolsUsed, got, tt.want)
-			}
-		})
-	}
-}
-
 func splitLines(s string) []string {
 	var lines []string
 	start := 0