[compiler-segfault (compiler-segfault)]

startCopyFromURL and copyFromURL in LokiBlobMetadataStore hand the new
blob the source's pageRangesInOrder and committedBlocksInOrder arrays
instead of copies of them. Both arrays are mutated in place: uploadPages,
clearRange and resizePageBlob rewrite the page range list, and
appendBlock pushes to the committed block list. The source and the copy end
up sharing one list, so:

• Copying a page blob and then writing a page to the copy changes what the
  source reads back, and the source's ETag does not change.
• Restoring a snapshot over its base blob and then writing to the restored
  blob changes what the snapshot reads back, so a backup is overwritten by the
  next write after a restore.
• Copying an append blob and then appending to the copy adds that block to the
  source as well, and the source's own next block is not visible.

Clone both lists when the destination blob is created, using the same shape
cloneBlobModel already uses, and reuse those helpers there. The chunks
themselves stay shared copy-on-write; only the lists that are mutated in place
are copied. The SQL metadata store is not affected, since it deserializes each
blob separately.

Three regression tests cover the page blob copy, the snapshot restore and the
append blob copy. All three fail on main and pass with the change.
pageblob.test.ts and appendblob.test.ts pass in full (100 passing, 1
pending), and eslint is clean.

Fixes #2890.

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