feat: auto generate GQL filters schema

[bonustrack]

Currently we need to type schema for any filter like this:

snapshot-hub/src/graphql/schema.gql

Lines 180 to 213 in f28d251

	input VoteWhere {
	id: String
	id_in: [String]
	ipfs: String
	ipfs_in: [String]
	space: String
	space_in: [String]
	voter: String
	voter_in: [String]
	proposal: String
	proposal_in: [String]
	reason: String
	reason_not: String
	reason_in: [String]
	reason_not_in: [String]
	app: String
	app_not: String
	app_in: [String]
	app_not_in: [String]
	created: Int
	created_in: [Int]
	created_gt: Int
	created_gte: Int
	created_lt: Int
	created_lte: Int
	vp: Float
	vp_in: [Float]
	vp_gt: Float
	vp_gte: Float
	vp_lt: Float
	vp_lte: Float
	vp_state: String
	vp_state_in: [String]
	}

Instead we should just define the GQL type schema and auto generate the filters, similar than on Checkpoint.