feat(ingestion): add wiki index rebuilder and audit log

ingestion/internal/wiki/log.go

@@ -0,0 +1,38 @@
+// ingestion/internal/wiki/log.go
+package wiki
+
+import (
+	"fmt"
+	"os"
+	"path/filepath"
+	"strings"
+)
+
+// AppendLog appends one ingestion record to brain/log.md.
+func AppendLog(brainDir, source string, pages, warnings []string, date string) error {
+	var sb strings.Builder
+	fmt.Fprintf(&sb, "## %s — ingest\n\n", date)
+	fmt.Fprintf(&sb, "- **Source:** %s\n", source)
+	if len(pages) > 0 {
+		sb.WriteString("- **Pages written:**\n")
+		for _, p := range pages {
+			fmt.Fprintf(&sb, "  - %s\n", p)
+		}
+	}
+	if len(warnings) > 0 {
+		sb.WriteString("- **Warnings:**\n")
+		for _, w := range warnings {
+			fmt.Fprintf(&sb, "  - %s\n", w)
+		}
+	}
+	sb.WriteString("\n")
+
+	logPath := filepath.Join(brainDir, "log.md")
+	f, err := os.OpenFile(logPath, os.O_APPEND|os.O_CREATE|os.O_WRONLY, 0o644)
+	if err != nil {
+		return fmt.Errorf("open log: %w", err)
+	}
+	defer f.Close()
+	_, err = f.WriteString(sb.String())
+	return err
+}