server: catch one more "PPLS" → "crop-chem-docs" rename miss in corpus_status header

Functional smoke test from trashpanda confirmed end-to-end working:
  $ docker run -d ... git.jpaul.io/justin/crop-chem-docs:corpus-2026.05.24
  $ docker exec ... python -c 'from docs_mcp.server import corpus_status; print(corpus_status())'

Output: 4,159 labels on disk (4,068 epa_ppls + 91 bayer), 216,467
chunks in Chroma collection `crop_chem_docs`, BM25 db 416 MB,
HYBRID_SEARCH=on, RERANK_URL=http://10.10.1.65:8082. Image is
production-ready for Drawbar compose.

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

docs_mcp/server.py

@@ -541,7 +541,7 @@ def corpus_status() -> str:
     Cheap — no embedder call.
     """
     with TimedCall("corpus_status", {}) as _call:
-        lines: list[str] = ["# PPLS corpus status\n"]
+        lines: list[str] = ["# crop-chem-docs corpus status\n"]
 
         # On-disk corpus
         labels_by_source: dict[str, int] = {}