Delete superseded run (recipe fingerprint changed with the run-identity fix)

Fix run identity and mid-run progress reporting

Best held-out checkpoint at 291,504,128 tokens

Advance latest checkpoint to 291,504,128 tokens

Stage checkpoint at 291,504,128 tokens

Best held-out checkpoint at 250,085,376 tokens

Advance latest checkpoint to 250,085,376 tokens

Stage checkpoint at 250,085,376 tokens

Initialize experiment run c4cd0856-69c4-42d9-9a1b-b278a89c46d5

Add Experiment1-C training source (architecture v3, verified)

initial commit