Create a project designed for use with the Toolforge build service[0]
that wraps the upstream matterbridge project[1] in a thin shell and
packages it with configuration matching the unpublished config built up
over the last ~5 years by the bridgebot tool.

This initial version also attempts to fix the long standing issue of BNC
reconnection to the upstream IRC network triggering duplicate IRC
channel message handling by building via a patched version of
matterbridge v1.26.0[2] that attempts to clear existing IRC event handlers
before adding new ones.

[0]: <https://wikitech.wikimedia.org/wiki/Help:Toolforge/Build_Service>
[1]: <https://github.com/42wim/matterbridge>
[2]: <https://gitlab.wikimedia.org/toolforge-repos/bridgebot-matterbridge/-/commit/38c64944bf1d67a0b3aaa765c3deb4d0200b24d6>

Bug: T363028
Bug: T305487