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/time.txt

@@ -0,0 +1,23 @@
+	Command being timed: "timeout -k 15 600 pi -p -a --provider entrim --model Qwen/Qwen3.6-35B-A3B --session-dir /tmp/rehearsal/runs/B+Q/session --name rehearsal-B+Q Read AGENTS.md in this directory and execute the refactoring task it describes. Run mvn -q test after each change. When done, stop and report the final diff of LongRangeForecasts.java."
+	User time (seconds): 22.32
+	System time (seconds): 1.63
+	Percent of CPU this job got: 32%
+	Elapsed (wall clock) time (h:mm:ss or m:ss): 1:12.70
+	Average shared text size (kbytes): 0
+	Average unshared data size (kbytes): 0
+	Average stack size (kbytes): 0
+	Average total size (kbytes): 0
+	Maximum resident set size (kbytes): 255980
+	Average resident set size (kbytes): 0
+	Major (requiring I/O) page faults: 0
+	Minor (reclaiming a frame) page faults: 474539
+	Voluntary context switches: 45190
+	Involuntary context switches: 1059
+	Swaps: 0
+	File system inputs: 0
+	File system outputs: 2072
+	Socket messages sent: 0
+	Socket messages received: 0
+	Signals delivered: 0
+	Page size (bytes): 4096
+	Exit status: 0