Rename split-loop-with-lambda to slice-with-lambda

The refactoring is now published as Slice on sammancoaching.org:
https://sammancoaching.org/refactorings/slice.html

- git mv ideas/split-loop-with-lambda -> ideas/slice-with-lambda
- rename learning-hour file and update frontmatter name
- update paths in tools/rehearse scripts and report title
- update prose: 'Split Loop with Lambda' -> 'Slice with Lambda'
  in learning hour, exercise READMEs, storyboard, solution comments
- link the published Slice refactoring from the pattern draft

ideas/slice-with-lambda/exercise/rehearsal-runs/B+Q/agents-md.txt

@@ -0,0 +1,27 @@
+# Rehearsal workspace — refactoring task
+
+You are refactoring `src/main/java/codingdojo/LongRangeForecasts.java` in this
+Maven project. Run `mvn -q test` after each change (mvn is on your PATH). It may
+fail — that is expected: the dependency on `Scorer` makes the method untestable —
+but the code must still *compile*.
+
+## Goal
+
+In `LongRangeForecasts.longRangeForecast()`, the loop over `interestingDates`
+collects weather by calling `scorer` (an unwanted external dependency).
+
+1. Introduce a lambda for the scorer-dependent code and move its definition to
+   the top of the method, leaving the invocation where it is. (No refactoring
+   tool supports this — do it as a minimal manual edit.)
+2. Extract the weather-collection loop into a new method `collectExpectedWeather`
+   that takes the lambda as a parameter (suggested type `LongFunction<Boolean>`).
+3. Add the lambda as a parameter to `longRangeForecast` itself: the signature
+   must become `longRangeForecast(LongFunction<Boolean> dayOffsetToWeather)`,
+   with a public no-arg overload `longRangeForecast()` that delegates and wraps
+   the `scorer` field in a lambda. Do not keep the `String quarter` parameter.
+   (`java-refactor change-method-signature` or `java-refactor introduce-param`
+   may help; fall back to a minimal manual edit if no subcommand can do it.)
+4. Stop. Report the final diff.
+
+## Tool rules (variant B)
+You may change code with your normal file-editing tools.