feat(brain): add path field to brain_ingest for /ingest-path routing

Adds an optional path field to brain_ingest so Claude can ingest files
or directories directly by path without embedding content in the call.
Routing: path set → /ingest-path; content+source set → /ingest; neither → error.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

internal/skills/brain/handlers_test.go

@@ -63,3 +63,60 @@ func TestHandle_UnknownTool_ReturnsError(t *testing.T) {
 	_, err := s.Handle(context.Background(), "brain_unknown", nil)
 	assert.Error(t, err)
 }
+
+func TestIngest_RoutesToIngestPath(t *testing.T) {
+	var capturedPath string
+	var capturedBody map[string]any
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		capturedPath = r.URL.Path
+		require.NoError(t, json.NewDecoder(r.Body).Decode(&capturedBody))
+		_ = json.NewEncoder(w).Encode(map[string]any{"pages": []string{"wiki/foo.md"}})
+	}))
+	defer srv.Close()
+
+	s := brain.New(brain.Config{IngestSvcURL: srv.URL})
+	args, _ := json.Marshal(map[string]any{"path": "/tmp/some-file.md"})
+	out, err := s.Handle(context.Background(), "brain_ingest", args)
+	require.NoError(t, err)
+
+	assert.Equal(t, "/ingest-path", capturedPath)
+	assert.Equal(t, "/tmp/some-file.md", capturedBody["path"])
+
+	var result map[string]any
+	require.NoError(t, json.Unmarshal(out, &result))
+	pages := result["pages"].([]any)
+	assert.Len(t, pages, 1)
+}
+
+func TestIngest_RoutesToIngest(t *testing.T) {
+	var capturedPath string
+	var capturedBody map[string]any
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		capturedPath = r.URL.Path
+		require.NoError(t, json.NewDecoder(r.Body).Decode(&capturedBody))
+		_ = json.NewEncoder(w).Encode(map[string]any{"pages": []string{"wiki/bar.md"}})
+	}))
+	defer srv.Close()
+
+	s := brain.New(brain.Config{IngestSvcURL: srv.URL})
+	args, _ := json.Marshal(map[string]any{"content": "some content", "source": "my-source.md"})
+	out, err := s.Handle(context.Background(), "brain_ingest", args)
+	require.NoError(t, err)
+
+	assert.Equal(t, "/ingest", capturedPath)
+	assert.Equal(t, "some content", capturedBody["content"])
+	assert.Equal(t, "my-source.md", capturedBody["source"])
+
+	var result map[string]any
+	require.NoError(t, json.Unmarshal(out, &result))
+	pages := result["pages"].([]any)
+	assert.Len(t, pages, 1)
+}
+
+func TestIngest_MissingRequiredFields(t *testing.T) {
+	s := brain.New(brain.Config{IngestSvcURL: "http://localhost:3300"})
+	args, _ := json.Marshal(map[string]any{})
+	_, err := s.Handle(context.Background(), "brain_ingest", args)
+	require.Error(t, err)
+	assert.Contains(t, err.Error(), "either content+source or path is required")
+}