[gql][2/n] output nodes estimation (MystenLabs#15497)

## Description 

Implements output nodes estimation. A node adds a cost of 1, unless it
is a connection field, where it would then have a cost of
default_page_size, or min(first, last) if so provided. This is
multiplicative - at the next child connection, that child's estimated
output will be multiplied with its parent's to yield the cumulative
result. A connection's pageInfo field does not multiplicatively increase the current count, as there is only one node for the entire connection.

## Test Plan 

1. check that we get this back in the headers when showUsage is provided
4. output_node_estimation.move

---
If your changes are not user-facing and not a breaking change, you can
skip the following section. Otherwise, please indicate what changed, and
then add to the Release Notes section as highlighted during the release
process.

### Type of Change (Check all that apply)

- [ ] protocol change
- [ ] user-visible impact
- [ ] breaking change for a client SDKs
- [ ] breaking change for FNs (FN binary must upgrade)
- [ ] breaking change for validators or node operators (must upgrade
binaries)
- [ ] breaking change for on-chain data layout
- [ ] necessitate either a data wipe or data migration

### Release notes

Cargo.toml

@@ -235,6 +235,7 @@ arc-swap = { version = "1.5.1", features = ["serde"] }
 assert_cmd = "2.0.6"
 async-graphql = "6.0.7"
 async-graphql-axum = "6.0.7"
+async-graphql-value = "6.0.7"
 async-recursion = "1.0.4"
 async-trait = "0.1.61"
 atomic_float = "0.1"

crates/sui-graphql-e2e-tests/tests/call/simple.exp

@@ -75,7 +75,7 @@ Response: {
 task 15 'run-graphql'. lines 68-74:
 Headers: {
     "content-type": "application/json",
-    "content-length": "136",
+    "content-length": "157",
     "x-sui-rpc-version": "0.1.0",
 }
 Service version: 0.1.0
@@ -87,7 +87,8 @@ Response: {
   },
   "extensions": {
     "usage": {
-      "nodes": 2,
+      "inputNodes": 2,
+      "outputNodes": 2,
       "depth": 2,
       "variables": 0,
       "fragments": 0,