Migrate all project files from repo root into prj/<name>/

Moved all 40 existing projects' .prj/.dat files (Layer weights, training
batches, legacy .weights.dat/.test.dat artifacts) from the flat repo root
into their own prj/<name>/ folder via git mv, matching the new path
convention from the previous commit. Filenames are unchanged, only the
directory. Non-project files at root (CLAUDE.md, Makefile, batch/moby
text corpora, the stray Layer.0.training.mat) were left in place.

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_016K8Gu7Qejd11JbdiHZqYAs

mnist_deep.Layer.2.bh.dat

@@ -1,3 +0,0 @@
-ARMA_MAT_TXT_FN008
-1 16
-  -2.2955861091613770e+00  -1.3443289995193481e+00   4.4173300266265869e-01  -2.0296111106872559e+00  -1.7269999952986836e-03  -2.7126030921936035e+00  -1.4476909637451172e+00  -3.3935520648956299e+00  -3.5313899517059326e+00  -6.1411899328231812e-01  -8.8638699054718018e-01  -3.0841898918151855e-01  -2.6406100392341614e-01  -1.8115940093994141e+00  -2.6898350715637207e+00  -2.0945470333099365e+00