Reduce the size of `bun.webcore.Blob` from 120 bytes to 96. Also make it
ref-counted: in-progress work on improving the bindings generator
depends on this, as it means C++ can pass a pointer to the `Blob` to Zig
without risking it being destroyed if the GC collects the associated
`JSBlob`.
Note that this PR depends on #23013.
(For internal tracking: fixes STAB-1289, STAB-1290)
Replace `catch bun.outOfMemory()`, which can accidentally catch
non-OOM-related errors, with either `bun.handleOom` or a manual `catch
|err| switch (err)`.
(For internal tracking: fixes STAB-1070)
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Co-authored-by: Dylan Conway <dylan.conway567@gmail.com>
