It seems a lot of time in our trial tests goes towards setting up the
database. (The same is probably true of Complement too)
We haven't done a full schema for about 20 schema versions, so no
surprise!
As a result, I want to produce a full schema soon.
In this PR I dust off `make_full_schema.sh` (which seems to have broken
after some SQLite changes)
and add a CI workflow that runs it (producing a diff) when someone
changes the schema.
The CI workflow also adds a sticky comment showing the diff on the
schema, so you can better appreciate the final effect of a change.
---
**Dead changes:**
I wanted to make it possible to generate a versioned full schema without
the manual work,
but you can't run the background updates without essentially starting up
a homeserver,
at which point it might fail because you haven't run all the deltas yet.
There's no actual good way to do this, short of deleting the latest
deltas (+ tweaking code to not crash without them)
or rolling back in the git history.
Backed out those changes, but they're preserved on the PR if interesting.
---------
Signed-off-by: Olivier 'reivilibre <oliverw@matrix.org>
