Multi-line DefaultValue, comments and attributes lose their indent after the first line: a nested field's [\n\t1,\n] initialiser drops to column 1 #132

What happens

TemplateBase.WriteDefaultValueTo (CodeBlocker/Templates/TemplateBase.cs:96), AddComments (:157), and AddAttributes (:184) all pass the caller's string straight to CodeBlocker.Write / WriteLine. IndentedTextWriter adds the indent only after its own WriteLine. It does not add it after a line break embedded in the text. The first line of a multi-line value is indented, and every later line starts at the indent the caller happened to type, usually none.

Repro (class C nested in Outer, so members sit at two tabs):

new FieldTemplate { Type = "int[]", Name = "xs", DefaultValue = "[\n\t1,\n\t2,\n]" }
new FieldTemplate { Type = "int", Name = "y", Comments = { "// line a\n// line b" } }

Observed (→ = tab):

→→int[] xs = [
→1,
→2,
];

→→// line a
// line b
→→int y;

If DefaultValue contains CRLF and the writer uses LF, or the other way round, the output also mixes line endings. That breaks the byte-identical output #81 established, along the same lines as #123 does for bodies.

Why it matters

The templates exist so callers do not have to manage indentation. The most common multi-line DefaultValue is a collection or object initialiser, and it comes out misaligned whenever the member is nested or sits under a namespace scope. A generator that commits its output then shows formatting churn, or a formatter has to clean up after it. The output still compiles, so this is a layout defect, not a correctness one.

#112 fixed this same problem for expression bodies only (WriteExpressionBody). The three paths above were left out.

Suggested fix

• Route DefaultValue, each comment, and each attribute through the same splice used for expression bodies (TemplateRendering.SpliceFragment). The first line stays on the declaration line, and each following line is written with WriteLine so it picks up the current indent.
• Normalise line endings first, the way DocComment.SplitLines does.
• Leave DefaultValueIsQuoted values alone. QuoteStringLiteral already escapes \n, so they are safe.
• Coordinate with Template bodies re-indent every line of a multi-line verbatim string, silently changing the generated string's value #121. Re-indenting a raw DefaultValue that holds a multi-line verbatim or raw string literal would change the string's value. Either reuse Template bodies re-indent every line of a multi-line verbatim string, silently changing the generated string's value #121's string-literal awareness, or skip re-indenting lines that fall inside such a literal.

Acceptance criteria

• A nested field with DefaultValue = "[\n\t1,\n\t2,\n]" renders each continuation line at the field's indent plus the value's own relative indent.
• A multi-line comment string and a multi-line attribute render every line at the member's indent.
• CRLF inside any of the three values produces only the writer's NewLine in the output.
• Tests cover all three paths, both nested and at top level.

Related, but none of them covers these paths: #112 (closed, expression bodies), #123 (body line endings), #121 (verbatim strings in bodies), #126 (blank line after Write("")).