Apply the review's wording fixes to the json_view documentation

- Copying is disabled because of its cost, not because of two documents
  borrowing the same buffer; the unique_ptr follows from move-only.
- Inputs: streams, FILE*, and wide characters (strings, arrays, pointers)
  are all supported and owned; point to parse_copy() for owned copies.
- The error replay only runs for failing input, builds no values, and is
  skipped with allow_exceptions = false.
- read() writes copied inputs into the previous owned copy.
- Views can dangle like std::string_view, and why there is no
  shared/weak pointer design.
- The 4 GiB limit (16-byte nodes, 16-byte scanner steps), streams being
  read to the end first, which macros apply, why materialize() has no
  source positions, and wording nits (accept() vs basic_json::accept(),
  is_binary, is_discarded, see-also lists, size table, "back into").

Signed-off-by: Niels Lohmann <mail@nlohmann.me>

docs/mkdocs/docs/api/basic_json_document/read.md

@@ -47,7 +47,9 @@ Every view taken from `#!cpp *this` before the call -- including the previous [`
 whether or not the new parse succeeds; take fresh views from [`root()`](root.md) afterward.
 
 `input` is borrowed or owned by the same rules as [`parse()`](parse.md#notes); a document can borrow on one call and
-own on the next, since ownership is decided freshly each time.
+own on the next, since ownership is decided freshly each time. An input that is copied (see the table in
+[`parse()`](parse.md#notes)) is written into the document's previous owned copy, reusing its memory; a moved-in
+`#!cpp std::string` replaces it.
 
 An integer argument that is not a `#!cpp bool` where the flags are expected, such as `#!cpp read(ptr, len)`, does not
 compile; see [`parse`](parse.md#notes).