core (main): Let plugins have several handlers + various improvements: `get_handler` can now return several handlers, which is notably useful for component with several included services. Various improvements such move to `async` method, docstring/type hints update, and slight improvment of SatXMPPComponent. rel 453

syntax: glob
bridge_constructor/generated
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ctags_links/
dist/
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libervia_backend.egg-info/
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twisted/plugins/dropin.cache
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