Add support for (make base64.wasm=1), which embeds sqlite3.wasm into its correspondin...

Add support for (make base64.wasm=1), which embeds sqlite3.wasm into its corresponding JS file as base64. A very expensive calculator which was fed the resulting file sizes assures me that the two-file approach is, in the aggregate, more efficient both in terms of overall network bandwidth (+~20% bigger for base64) and client-side memory usage (streaming vs non-streaming wasm compilation), so we'll shelve this as an interesting experiment or maybe for use by custom builds.

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