Add NYISO supply ancillary MC generation capability

Adds the ability to generate NY supply ancillary marginal costs from NYISO
ancillary-services clearing prices, without changing any published RIE/NY
results and without enforcing ancillary on existing runs.

- data/nyiso/ancillary/: fetch/validate/update pipeline for NYISO AS prices
  (mirrors data/isone/ancillary/ conventions).
- supply_ancillary.py / generate_supply_ancillary_mc.py: --iso nyiso support
  (NYISO regulation capacity + movement). ISO-NE path is behavior-preserving.
- supply_utils.py: DEFAULT_NYISO_ANCILLARY_S3_BASE.
- ny/Justfile: opt-in create-supply-ancillary-mc-data[-all] recipes (not wired
  into create-supply-mc-data). Enable a run later by setting SUPPLY_ANCILLARY_MC.
- Tests for the NYISO transform and ancillary end-use computation.

Refs #396.

Co-authored-by: Cursor <cursoragent@cursor.com>

Author: alxsmith

data/nyiso/ancillary/Justfile

@@ -0,0 +1,47 @@
+# NYISO ancillary service clearing prices (day-ahead hourly + real-time 5-min AS)
+#
+# Same recipe shape as data/isone/ancillary/Justfile: fetch, validate, prepare,
+# upload, update, clean. Default ``markets=rt`` (5-minute real-time)—finest MIS
+# resolution. Override: ``markets=dam`` (hourly day-ahead) or ``markets=both``.
+#
+# Run from repo root: just -f data/nyiso/ancillary/Justfile <recipe>
+# Or from this dir:   just <recipe>
+
+path_local_repo := `git rev-parse --show-toplevel`
+path_local_base := justfile_directory()
+path_local_parquet := path_local_base + "/parquet"
+
+# Mirror ISO-NE: s3://data.sb/isone/ancillary/ → s3://data.sb/nyiso/ancillary/
+
+path_s3_parquet := "s3://data.sb/nyiso/ancillary/"
+start := "2010-01"
+end := ""
+markets := "rt"
+
+fetch:
+    uv run python "{{ path_local_base }}/fetch_nyiso_as_prices_parquet.py" \
+        --start "{{ start }}" --end "{{ end }}" \
+        --path-local-parquet "{{ path_local_parquet }}" \
+        --markets "{{ markets }}"
+
+validate:
+    uv run python "{{ path_local_base }}/validate_nyiso_as_prices_parquet.py" \
+        --path-local-parquet "{{ path_local_parquet }}"
+
+prepare: fetch validate
+
+# Upload: syncs whatever is under parquet/ (resolution is determined at fetch time).
+upload:
+    aws s3 sync "{{ path_local_parquet }}/" "{{ path_s3_parquet }}" \
+        --exclude "*" --include "*.parquet"
+    @echo "Uploaded to {{ path_s3_parquet }}"
+
+update:
+    uv run python "{{ path_local_base }}/update_nyiso_as_prices_to_latest.py" \
+        --path-local-parquet "{{ path_local_parquet }}" \
+        --path-s3-parquet "{{ path_s3_parquet }}" \
+        --markets "{{ markets }}"
+
+clean:
+    rm -rf "{{ path_local_parquet }}"
+    @echo "Removed parquet/"