feat(cache): redis cache (#8822)

# Which Problems Are Solved

Add a cache implementation using Redis single mode. This does not add
support for Redis Cluster or sentinel.

# How the Problems Are Solved

Added the `internal/cache/redis` package. All operations occur
atomically, including setting of secondary indexes, using LUA scripts
where needed.

The [`miniredis`](https://github.com/alicebob/miniredis) package is used
to run unit tests.

# Additional Changes

- Move connector code to `internal/cache/connector/...` and remove
duplicate code from `query` and `command` packages.
- Fix a missed invalidation on the restrictions projection

# Additional Context

Closes #8130

internal/cache/pruner_test.go

@@ -30,7 +30,7 @@ func TestAutoPruneConfig_startAutoPrune(t *testing.T) {
 		called: make(chan struct{}),
 	}
 	clock := clockwork.NewFakeClock()
-	close := c.startAutoPrune(ctx, &pruner, "foo", clock)
+	close := c.startAutoPrune(ctx, &pruner, PurposeAuthzInstance, clock)
 	defer close()
 	clock.Advance(time.Second)