runtime(yaml): improve syntax highlighting for YAML
- Recognize block scalar style to avoid unexpected highlighting by `yamlFlowString` (fix #11517)
- Improve performance of `yamlFlowMappingKey` by allowing execution by the NFA engine (fix #10730)
- It was intentionally disabled before patterns were optimized by `s:SimplifyToAssumeAllPrintable`.
- Fix detection of flow style mapping indicators (fix #8234).
- Enable highlighting of explicit mapping value indicators and node properties in flow style.
- Add syntax highlighting tests
closes: #14354
Signed-off-by: itchyny <itchyny@cybozu.co.jp>
Signed-off-by: Christian Brabandt <cb@256bit.org>
diff --git a/runtime/syntax/testdir/dumps/yaml_07.dump b/runtime/syntax/testdir/dumps/yaml_07.dump
new file mode 100644
index 0000000..a21684f
--- /dev/null
+++ b/runtime/syntax/testdir/dumps/yaml_07.dump
@@ -0,0 +1,20 @@
+| +0&#ffffff0@74
+|m+0#00e0e07&|a|p@1|i|n|g| |m|e|r|g|e|:+0#e000e06&| +0#0000000&@60
+@2|f+0#00e0e07&|o@1|:+0#e000e06&| +0#0000000&|&+0#00e0003&|f|o@1| +0#0000000&@63
+@4|b+0#00e0e07&|a|r|:+0#e000e06&| +0#0000000&|b|a|z| @62
+@2|b+0#00e0e07&|a|r|:+0#e000e06&| +0#0000000&@68
+@4><+0#e000e06&@1|:| +0#0000000&|*+0#00e0003&|f|o@1| +0#0000000&@62
+@4|b+0#00e0e07&|a|z|:+0#e000e06&| +0#0000000&|&+0#00e0003&|b|a|r| +0#0000000&@61
+@6|f+0#00e0e07&|o@1|:+0#e000e06&| +0#0000000&|[+0#e000e06&|*+0#00e0003&|f|o@1|]+0#e000e06&| +0#0000000&@57
+@4|q+0#00e0e07&|u|x|:+0#e000e06&| +0#0000000&@66
+@6|<+0#e000e06&@1|:| +0#0000000&|[+0#e000e06&|*+0#00e0003&|f|o@1|,+0#0000000&| |*+0#00e0003&|b|a|r|]+0#e000e06&| +0#0000000&@52
+@2|b+0#00e0e07&|a|z|:+0#e000e06&| +0#0000000&|{+0#e000e06&|<@1|:| +0#0000000&|*+0#00e0003&|f|o@1|,+0#0000000&| |q+0#00e0e07&|u|x|:+0#e000e06&| +0#0000000&|[+0#e000e06&|{|<@1| +0#0000000&|:+0#e000e06&| +0#0000000&|*+0#00e0003&|f|o@1|}+0#e000e06&|]|}| +0#0000000&@37
+|~+0#4040ff13&| @73
+|~| @73
+|~| @73
+|~| @73
+|~| @73
+|~| @73
+|~| @73
+|~| @73
+| +0#0000000&@56|1|2|7|,|5| @8|B|o|t|