feat(server): wire claudewatcher behind CLAUDE_SESSIONS_DIR

Opt-in by setting CLAUDE_SESSIONS_DIR to the ~/.claude/projects path.
When set, the server starts claudewatcher.Watch in a goroutine that
ticks every CLAUDE_INGEST_INTERVAL seconds (default 60). Requires
BRAIN_PG_DSN for the cursor table — fail-fast if missing.

Each Batch becomes one wiki note at:
  brain/wiki/claude-sessions/facts/session-<host>-<session_id>.md

with frontmatter type=source + domain=<project basename>. Per-turn
content capped at 2000 chars (full transcripts stay in
~/.claude/projects already); the brain entry is a digest, not a
mirror.

CLAUDE_INGEST_HOST overrides the os.Hostname()-derived host label,
useful when multiple ingestion pods consume the same DSN from
different machines.

Closes hyperguild#27.

Bump-Type: minor

ingestion/cmd/server/main.go

@@ -15,6 +15,7 @@ import (
 	chassisauth "gitea.d-ma.be/mathias/mcp-chassis/auth"
 
 	"github.com/mathiasbq/hyperguild/ingestion/internal/api"
+	"github.com/mathiasbq/hyperguild/ingestion/internal/claudewatcher"
 	"github.com/mathiasbq/hyperguild/ingestion/internal/embed"
 	"github.com/mathiasbq/hyperguild/ingestion/internal/graphstore"
 	"github.com/mathiasbq/hyperguild/ingestion/internal/graphsync"
@@ -29,6 +30,50 @@ import (
 	"github.com/mathiasbq/hyperguild/ingestion/internal/watcher"
 )
 
+// claudeSink converts each claudewatcher.Batch into one wiki note under
+// brain/wiki/claude-sessions/facts/. v1 emits one note per session
+// keyed by host + session id; classifier-driven hall routing is a
+// follow-up (hyperguild#27 v2).
+type claudeSink struct {
+	brainDir string
+	logger   *slog.Logger
+}
+
+func (s *claudeSink) Ingest(ctx context.Context, b claudewatcher.Batch) error {
+	if len(b.Turns) == 0 {
+		return nil
+	}
+	var sb strings.Builder
+	fmt.Fprintf(&sb, "# Claude session %s (%s)\n\n", b.SessionID, b.Host)
+	fmt.Fprintf(&sb, "_Project: `%s`. File: `%s`. Turns: %d._\n\n", b.ProjectID, b.FilePath, len(b.Turns))
+	for _, t := range b.Turns {
+		fmt.Fprintf(&sb, "## %s — %s\n\n", t.Type, t.Timestamp.UTC().Format(time.RFC3339))
+		if t.ToolName != "" {
+			fmt.Fprintf(&sb, "_tool: `%s`_\n\n", t.ToolName)
+		}
+		// Cap per-turn excerpt to keep page size bounded; the full
+		// transcript lives on disk under ~/.claude/projects/ already.
+		content := t.Content
+		if len(content) > 2000 {
+			content = content[:2000] + "…"
+		}
+		sb.WriteString(content)
+		sb.WriteString("\n\n")
+	}
+	slug := "session-" + b.Host + "-" + b.SessionID
+	if _, err := api.WriteNote(s.brainDir, api.WriteNoteOptions{
+		Filename: slug,
+		Wing:     "claude-sessions",
+		Hall:     "facts",
+		Type:     "source",
+		Domain:   b.ProjectID,
+		Content:  sb.String(),
+	}); err != nil {
+		return fmt.Errorf("write claude session note: %w", err)
+	}
+	return nil
+}
+
 // redactDSN parses a Postgres URL and replaces its password with `***`
 // for safe inclusion in logs. Falls back to a non-leaking placeholder
 // if parsing fails — we never log a raw DSN.
@@ -73,6 +118,16 @@ func envInt(key string, fallback int) int {
 	return fallback
 }
 
+// systemHostname returns os.Hostname() with a "unknown" fallback so the
+// caller never has to handle the rare error path.
+func systemHostname() string {
+	h, err := os.Hostname()
+	if err != nil || h == "" {
+		return "unknown"
+	}
+	return h
+}
+
 func main() {
 	logger := slog.New(slog.NewJSONHandler(os.Stdout, nil))
 
@@ -191,6 +246,43 @@ func main() {
 			Pipeline: pipelineCfg,
 		})
 	}
+
+	// Claude Code session ingestion (hyperguild#27 / infra#73 Track E.1).
+	// Off by default — explicitly opt in by setting CLAUDE_SESSIONS_DIR
+	// to the ~/.claude/projects path. Requires BRAIN_PG_DSN for the
+	// cursor table (resumable offsets across restarts).
+	if claudeDir := os.Getenv("CLAUDE_SESSIONS_DIR"); claudeDir != "" {
+		if pgDSN == "" {
+			logger.Error("CLAUDE_SESSIONS_DIR set but BRAIN_PG_DSN missing — claudewatcher needs the cursor table")
+			os.Exit(1)
+		}
+		cursorStore, cerr := claudewatcher.NewCursorStore(ctx, pgDSN)
+		if cerr != nil {
+			logger.Error("claudewatcher cursor init", "err", cerr)
+			os.Exit(1)
+		}
+		if cerr := cursorStore.Init(ctx); cerr != nil {
+			logger.Error("claudewatcher cursor migrate", "err", cerr)
+			os.Exit(1)
+		}
+		host := envOr("CLAUDE_INGEST_HOST", systemHostname())
+		interval := time.Duration(envInt("CLAUDE_INGEST_INTERVAL", 60)) * time.Second
+		sink := &claudeSink{brainDir: brainDir, logger: logger}
+		go func() {
+			if err := claudewatcher.Watch(ctx, claudewatcher.Config{
+				SessionsDir: claudeDir,
+				Host:        host,
+				Interval:    interval,
+				Sink:        sink,
+				Cursors:     cursorStore,
+				Logger:      logger,
+			}); err != nil && err != context.Canceled {
+				logger.Error("claudewatcher exited", "err", err)
+			}
+		}()
+		logger.Info("claudewatcher started",
+			"sessions_dir", claudeDir, "host", host, "interval", interval)
+	}
 	if vectorStore != nil {
 		embedSyncInterval := envInt("BRAIN_EMBED_SYNC_INTERVAL", 300)
 		vectorstore.StartSync(ctx, brainDir, vectorStore,