lexgen: incorporate new tools.ozone namespace; bunch of old lexicons …

…deprecated (#617)

DO NOT MERGE YET

This is based off the atproto PR:
bluesky-social/atproto#2288

Does mostly expected things, adding `api/ozone` for tools.ozone.*
namespace. Easier than expected because no records in that namespace, so
no cborgen needed.

There are some cborgen changes rolled up in this PR. I think I didn't
commit changes to at least the bsky codegen, something about string and
pointer-to-string. I assume those are unrelated to the namespace stuff
and should be resolved in a separate clean PR.

~I haven't self-reviewed or tested this at all, should do that before
merging or deploying. I *think* I caught all the string constants with
`com.atproto.admin.defs#whatever` in code, but there might be more
lurking (these don't result in compile-time errors).~

Makefile

@@ -65,6 +65,7 @@ check: ## Compile everything, checking syntax (does not output binaries)
 lexgen: ## Run codegen tool for lexicons (lexicon JSON to Go packages)
 	go run ./cmd/lexgen/ --package bsky --prefix app.bsky --outdir api/bsky $(LEXDIR)
 	go run ./cmd/lexgen/ --package atproto --prefix com.atproto --outdir api/atproto $(LEXDIR)
+	go run ./cmd/lexgen/ --package ozone --prefix tools.ozone --outdir api/ozone $(LEXDIR)
 
 .PHONY: cborgen
 cborgen: ## Run codegen tool for CBOR serialization