ci: green pipelines that check what exists; one formatting contract

The Test Suite job failed on every push since the black check was added
because the tree had never been formatted, and pre-commit said 120
columns while CI ran black's default 88. pyproject.toml now carries
[tool.black] / [tool.isort] (88, black profile) as the single source;
pre-commit reads it; `make format` applied it (13 files, whitespace only,
146 insertions / 128 deletions, tests unchanged at 146 passed).

ci.yml: lint (black, isort, flake8 hard errors) + pytest. The Docker
registry push, VictoriaMetrics integration test, staging/production
deploy and Apache-Bench jobs were template scaffolding for hosts and
registries that do not exist; production is a systemd unit updated by
git pull. Removed rather than left permanently skipped.

docs.yml: the "Check markdown links" step curl'd every URL in every .md
and failed on localhost examples and the Tailscale IP, and the Sphinx
jobs built artifacts nobody read. Replaced by two checks that mean
something: relative links/images in README, CONTRIBUTING and docs/
resolve inside the repo, and the FastAPI OpenAPI schema exports with
the documented endpoints present (uploaded as an artifact).

src/ml/hii_rain.py

@@ -65,7 +65,12 @@ def load_gauge_mean(
             "AND s.longitude BETWEEN :lon_lo AND :lon_hi "
             "AND m.rain_1h IS NOT NULL"
         )
-        params = {"lat_lo": lat_lo, "lat_hi": lat_hi, "lon_lo": lon_lo, "lon_hi": lon_hi}
+        params = {
+            "lat_lo": lat_lo,
+            "lat_hi": lat_hi,
+            "lon_lo": lon_lo,
+            "lon_hi": lon_hi,
+        }
         if start is not None:
             query += " AND m.timestamp >= :start"
             params["start"] = pd.Timestamp(start).to_pydatetime()
@@ -98,9 +103,7 @@ def compare_with_openmeteo(
     Both are summed over trailing `window_h` so single-hour timing offsets
     (gauges report at :00, the model's hour is an interval) do not dominate.
     """
-    joined = pd.concat(
-        {"gauge": gauge, "openmeteo": openmeteo}, axis=1
-    ).dropna()
+    joined = pd.concat({"gauge": gauge, "openmeteo": openmeteo}, axis=1).dropna()
     if joined.empty:
         return {"overlap_hours": 0}
     g = joined["gauge"].rolling(window_h, min_periods=window_h).sum()