Improve array parsing and rewriting in general and, in particular, while newline preservation is enabled.

Set type and preservation properties on PGPList elements during parsing; use properties during rewriting.

Improve pretty printing by increasing the indent after first newline when preserve newline is enabled.

Enhance parsing with newline but not whitespace preservation, particularly in array expressions. To facilitate this, remove trailing whitespace and comments from PGPOperand objects to improve consistency of grammar structure.