Exposing very hacky Wasm httplib replacement

[carlopi]

Idea is for wasm_httplib_replacement.hpp (or a less hacky version of it) to be part of duckdb/duckdb for 1.2, and expose a subset of HttpLib interface.

This will not, as of now, work in DuckDB-Wasm + node, I have the code also there but this is good enough to get started.

This is a simpler problem than evidence-dev/duckdb_gsheets#35, where a slightly more complex API needs to be mocked.

I have tested this in limited ways locally, and error detection / handling should likely improve (HandleHttpError just do nothing).

Demo:

[lmangani]

@carlopi

[carlopi]

Note that CORS is not correctly set up on gist.github.com, BUT there is a mirror with CORS enabled.

Once this is merged and in community extensions,

INSTALL webmacro FROM community;
LOAD webmacro;
SELECT load_macro_from_url('https://gist.githubusercontent.com/lmangani/518215a68e674ac662537d518799b893/raw/5f305480fdd7468f4ecda3686011bab8e8e711bf/bsky.sql') as res;
SELECT * FROM search_posts('qxip.bsky.social', text := 'quack');

Should work (but not the query on the readme)

But

SELECT load_macro_from_url('https://gist.github.com/lmangani/518215a68e674ac662537d518799b893/raw/5f305480fdd7468f4ecda3686011bab8e8e711bf/bsky.sql') as res;

will crash badly (since failures are not handled), let me fix it.

[carlopi]

Too late, anyhow, can also go in a separate PR, basically something need to be thrown in HandleHttpError, I will send a PR in a bit.

[lmangani]

Sorry I saw the tests complete and merged! Ready for the next PR and halted the community update until then

[lmangani]

I updated the readme example as suggested with githubusercontent