Add RiboCode intermediate test files

Add intermediate outputs from ribocode/prepare and ribocode/metaplots
modules to enable faster testing of downstream ribocode modules.

Files added:
- annotation/transcripts.pickle
- annotation/transcripts_cds.txt
- annotation/transcripts_sequence.fa
- test_pre_config.txt

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

Author: pinin4fjords

data/genomics/homo_sapiens/riboseq_expression/ribocode/README.md

@@ -0,0 +1,15 @@
+# RiboCode module test files
+
+Intermediate outputs for testing ribocode modules.
+
+## annotation/
+
+Output from `ribocode/prepare` module:
+
+- `transcripts.pickle` - Pickled transcript annotation data
+- `transcripts_cds.txt` - CDS information for transcripts
+- `transcripts_sequence.fa` - Transcript sequences in FASTA format
+
+## test_pre_config.txt
+
+P-site offset configuration file generated by `ribocode/metaplots` module.