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

prj/test/test.Layer.11.weights.dat

@@ -0,0 +1,11 @@
+4 1 2
+-0.003969
+0.000410
+0.004675
+-0.000105
+-0.001887
+0.003077
+0.000152 0.002643 
+0.004877 0.004297 
+-0.002147 0.002209 
+0.003226 0.004799