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, 53 deletions

diff --git a/workspaces/main/shaders/cnn/cnn_conv7x7.wgsl b/workspaces/main/shaders/cnn/cnn_conv7x7.wgsl
deleted file mode 100644
index e68d644..0000000
--- a/workspaces/main/shaders/cnn/cnn_conv7x7.wgsl
+++ /dev/null
@@ -1,53 +0,0 @@
-// 7x7 convolution with 49 samples
-// Applies mat4 weights per sample
-
-fn cnn_conv7x7(
-  tex: texture_2d<f32>,
-  samp: sampler,
-  uv: vec2<f32>,
-  resolution: vec2<f32>,
-  weights: array<mat4x4<f32>, 49>,
-  bias: vec4<f32>
-) -> vec4<f32> {
-  let step = 1.0 / resolution;
-  var sum = bias;
-  var idx = 0;
-
-  for (var dy = -3; dy <= 3; dy++) {
-    for (var dx = -3; dx <= 3; dx++) {
-      let offset = vec2<f32>(f32(dx), f32(dy)) * step;
-      let sample = textureSample(tex, samp, uv + offset);
-      sum += weights[idx] * sample;
-      idx++;
-    }
-  }
-
-  return sum;
-}
-
-fn cnn_conv7x7_with_coord(
-  tex: texture_2d<f32>,
-  samp: sampler,
-  uv: vec2<f32>,
-  resolution: vec2<f32>,
-  rgba_weights: array<mat4x4<f32>, 49>,
-  coord_weights: mat2x4<f32>,
-  bias: vec4<f32>
-) -> vec4<f32> {
-  let step = 1.0 / resolution;
-  var sum = bias;
-
-  sum += coord_weights * uv;
-
-  var idx = 0;
-  for (var dy = -3; dy <= 3; dy++) {
-    for (var dx = -3; dx <= 3; dx++) {
-      let offset = vec2<f32>(f32(dx), f32(dy)) * step;
-      let rgba = textureSample(tex, samp, uv + offset);
-      sum += rgba_weights[idx] * rgba;
-      idx++;
-    }
-  }
-
-  return sum;
-}