docs(paper): compile thermodynamic memory paper PDF (26 pages)

Final PDF artefact for publication. Whitelist in .gitignore so the
compiled binary lives alongside the LaTeX source. 26 pages, 380 KB,
pdfTeX-1.40.29, two compilation passes for cross-references.

Source: docs/arxiv-thermodynamic/main.tex (post §6.3 second pass at
6f75221: LME-S 17-row + LoCoMo 14-row two-baseline + per-category
specialization + cadence-fix narrative + plasticity-fix narrative).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: cdeust

.gitignore

@@ -23,6 +23,8 @@ benchmarks/longmemeval/longmemeval_s.json
 benchmarks/longmemeval/longmemeval_oracle.json
 benchmarks/spell_alteration/*.pdf
 *.pdf
+# Whitelist the thermodynamic memory paper PDF (compiled artefact for publication)
+!docs/arxiv-thermodynamic/main.pdf
 
 # Runtime telemetry
 traces/