Get rid of the Redis name, except where it's needed for API compatibility. This can be done once we have a name.

Some of the below changes have a low risk of breaking e.g. script parsing logs or INFO output, but I'd say those are acceptable.

• ☑️ Make variables REDIS_CFLAGS and REDIS_LDFLAGS. Done in 3863227. They were renamed to SERVER_*.

• Occurrences of "Redis" in comments #148

• Occurrences of "Redis" in error replies #204

• Occurrences of "Redis" in log entries #207

• Occurrences of "Redis" in command JSON files (src/commands/*.json) Untrademark json files #35

• The output of INFO server #41

  # Server
  redis_version:255.255.255
  redis_git_sha1:daadbca2
  redis_git_dirty:1
  redis_build_id:187c43196ce2ead2
  redis_mode:standalone
  

  We have two options:

  1. Change to "server_version" (etc.) and also add a "server_name:newname"
  2. Change the prefix, e.g. "newname_version", etc.

• The reply from HELLO #61

  > hello 3
  1# "server" => "redis"
  2# "version" => "7.2.4"
  (...)
  

• Client-side caching "__redis__:invalidate" #280

• Rename internal struct and function names (redisCommand, redisDb, etc.) #144

• Macros for including a file once, like #ifndef __REDIS_COMMANDS_H #137

• Rename src/redisassert.c to src/serverassert.c #134

• Rename redis.conf to valkey.conf #135

• Add Lua global object server as alias for redis #136

• Rename the binaries to redis-server, redis-sentinel, redis-check-rdb, redis-check-aof, redis-cli, redis-benchmark and their corresponding .c and .h files. Done in 3863227.

• Update references to the binaries (in scripts and tests) #153

• Create "redis" symlinks for the binaries in make install #147

• Add valkeymodule.h, ABI compatible with redismodule #146

• Change default pidfile #321

• Rename and change variable names in utils/redis_init_script #354