Avoid decoding warm-cache script responses into full UTF-16 SourceCode
buffers when a bytecode cache sidecar is available. SourceCode now keeps
the original immutable source bytes and source encoding, then decodes
only when full source text or a Function.toString() range is requested.
Compute the bytecode cache source hash while streaming decoded code
points from the response bytes, so cache validation does not force an
intermediate UTF-8 string. Function and class source text metadata now
stores SourceCode ranges instead of views into a materialized buffer.
Store source map locations as bytecode offset, line, and column.
Runtime consumers only emit the start line and column, so source end
positions and source text offsets do not need to be carried through
Executable source maps, bytecode cache serialization, or the Rust FFI.
Keep SourceCode's internal position cache able to track source text
offsets so callers can still translate source offsets to line and
column pairs when needed. Hash dump-bytecode IDs from the name, first
source position, and bytecode size instead of source slices that need
end offsets.
Bump the bytecode cache format version for the slimmer serialized
source map entry shape.
Report outline storage retained by scripts, environments, module
namespace objects, iterator helpers, property name iterators, argument
objects, and error tracebacks. These objects keep vectors and maps that
can grow independently from their GC cell sizes.
Split JS::ErrorData out of JS::Error so that it can be used both
by JS::Error and WebIDL::DOMException. This adds support for
Error.isError to DOMException, also letting us report DOMException
stack information to the console.
