archive(cnn): move CNN v1 to cnn_v1/ subdirectory

Consolidate CNN v1 (CNNEffect) into dedicated directory:
- C++ effect: src/effects → cnn_v1/src/
- Shaders: workspaces/main/shaders/cnn → cnn_v1/shaders/
- Training: training/train_cnn.py → cnn_v1/training/
- Docs: doc/CNN*.md → cnn_v1/docs/

Updated all references:
- CMake source list
- C++ includes (relative paths: ../../cnn_v1/src/)
- Asset paths (../../cnn_v1/shaders/)
- Documentation cross-references

CNN v1 remains active in timeline. For new work, use CNN v2 with
enhanced features (7D static, storage buffer, sigmoid activation).

Tests: 34/34 passing (100%)

1 files changed, 0 insertions, 18 deletions

diff --git a/workspaces/main/shaders/cnn/cnn_activation.wgsl b/workspaces/main/shaders/cnn/cnn_activation.wgsl
deleted file mode 100644
index 4fe771e..0000000
--- a/workspaces/main/shaders/cnn/cnn_activation.wgsl
+++ /dev/null
@@ -1,18 +0,0 @@
-// CNN activation functions
-// 4 functions: tanh, ReLU, sigmoid, leaky_relu
-
-fn cnn_tanh(x: vec4<f32>) -> vec4<f32> {
-  return tanh(x);
-}
-
-fn cnn_relu(x: vec4<f32>) -> vec4<f32> {
-  return max(vec4<f32>(0.0), x);
-}
-
-fn cnn_sigmoid(x: vec4<f32>) -> vec4<f32> {
-  return 1.0 / (1.0 + exp(-x));
-}
-
-fn cnn_leaky_relu(x: vec4<f32>, alpha: f32) -> vec4<f32> {
-  return max(alpha * x, x);
-}