Release reporter destination references after finalization

docs/roadmap/audit/catalog.md

@@ -1,6 +1,6 @@
 # Consolidated audit catalog
 
-Status: **20 distinct open findings: 20 P3**, consolidated from 30
+Status: **19 distinct open findings: 19 P3**, consolidated from 30
 numbered entries in seven audit documents. Reviewed audit state:
 `db732e3a1de55c844f77870e1c6db683c2685d5d`.
 
@@ -159,6 +159,10 @@ Also noted in the [documentation cross-references](13-documentation.md#previousl
 
 ## F07 — P3: Closed reporting handles retain both borrowed destinations
 
+**Complete.** Finalization drops direct destination references after presentation
+is captured. Focused reporter tests cover successful, failed and canceled outcomes,
+closed handles, retained causes, and caller ownership.
+
 A retained closed `Reporter`, `Output`, or `DeferredReporter` keeps the shared
 reporting state and both destination writers reachable. Applications retaining a
 closed handle can therefore retain large buffers or resource-bearing writer

docs/roadmap/implementation.md

@@ -1,6 +1,6 @@
 # Audit remediation implementation plan
 
-Status: in progress; Stages 1–6 complete.
+Status: in progress; Stages 1–7 complete.
 
 Baseline: `d492c7747175c01a53261206c2b4356e53453621`. Before this sprint,
 intervening changes recorded decisions and retired the completed older
@@ -280,6 +280,11 @@ script/shell validation. Stage 14 relies on this repaired fixture.
 
 ## Stage 7 — Release finalized reporter destination references
 
+**Complete.** Finalization clears both borrowed writer references after
+capturing presentation, without closing them. Tests cover success, operational
+failure, cancellation, late handles and writer ownership; focused reporter tests
+pass in the offline aligned Go 1.27.0 workspace with `-mod=readonly`.
+
 Findings: F07. Source: `reporter.go`; builds on stage 3.
 
 1. After deferred/completion/terminal presentation and capture of observations,

reporter.go

@@ -327,6 +327,8 @@ func (r *Reporter) finalize(outcome Outcome, completion func(*Reporter)) Outcome
 	state.closed = true
 	state.deferred = nil
 	outcome.Presentation = state.presentationLocked()
+	state.output.writer = nil
+	state.diagnostics.writer = nil
 	state.mu.Unlock()
 	return normalizeOutcome(outcome)
 }

reporter_test.go

@@ -2,6 +2,7 @@ package commandkit
 
 import (
 	"bytes"
+	"context"
 	"errors"
 	"io"
 	"strings"
@@ -710,3 +711,39 @@ func setReporterVisibility(reporter *Reporter, mode reportingMode, progress, pro
 	}
 	reporter.applySelection(selection)
 }
+
+func TestReporterFinalizationReleasesBorrowedDestinations(t *testing.T) {
+	cause := errors.New("operation failed")
+	for _, tc := range []struct {
+		name    string
+		outcome Outcome
+		cause   error
+	}{
+		{name: "success", outcome: Success()},
+		{name: "failure", outcome: Failure("failed").WithCause(cause), cause: cause},
+		{name: "cancellation", outcome: Failure("canceled").WithCause(context.Canceled), cause: context.Canceled},
+	} {
+		t.Run(tc.name, func(t *testing.T) {
+			out, diagnostics := &callerOwnedWriter{}, &callerOwnedWriter{}
+			reporter := newReporter(Streams{Out: out, Err: diagnostics})
+			output, deferred := reporter.Output(), reporter.AtEnd()
+			result := reporter.finalize(tc.outcome, nil)
+			if reporter.state.output.writer != nil || reporter.state.diagnostics.writer != nil || out.closeCalls != 0 || diagnostics.closeCalls != 0 || tc.cause != nil && !errors.Is(result.Cause, tc.cause) {
+				t.Fatalf("outcome=%#v state=%#v", result, reporter.state)
+			}
+			outLen, diagnosticLen := out.Len(), diagnostics.Len()
+			if _, err := output.Write([]byte("late")); !errors.Is(err, ErrReporterClosed) {
+				t.Errorf("output error=%v", err)
+			}
+			if err := reporter.Warn("late"); !errors.Is(err, ErrReporterClosed) {
+				t.Errorf("reporter error=%v", err)
+			}
+			if err := deferred.Warn("late"); !errors.Is(err, ErrReporterClosed) {
+				t.Errorf("deferred error=%v", err)
+			}
+			if out.Len() != outLen || diagnostics.Len() != diagnosticLen {
+				t.Fatal("late operation touched destinations")
+			}
+		})
+	}
+}