Cherry-pick failed with conflicts and requires manual resolution.
    This empty commit exists to allow opening a draft PR.

…query null regression (#8345)

Bumps `github.com/TykTechnologies/graphql-go-tools` to pick up
**TykTechnologies/graphql-go-tools#447**.

On a GraphQL Federation supergraph API, running a subscription
(websocket) first and then a query over the same connection makes the
query return `null` instead of data. Gateway logs show `websocket
upgrade for GraphQL engine failed: 'upgrade' token not found in
'Connection' header` against the subgraphs. Regression introduced in
5.8.15 / 5.13.1 / 5.14.0 (clean on 5.8.14 and 5.13.0).

The gateway tags an inbound websocket subscription request with a
context value `GraphQLIsWebSocketUpgrade=true`. The library change in
`mergedContext` that resolved values from that original request context,
so the flag leaked into every subgraph fetch. The subgraphs then tried
to perform a websocket handshake on plain HTTP fetches, which failed →
`null`.

The executor now builds its execution context without inheriting the
original request's context values, while still forwarding the
per-request header modifier — preserving TT-17442's per-user
connection/credential isolation. See #447 for details and tests.

- Bumps the **v1** module only (`v1.6.2-0.20260610093432-c7048b604e16` →
`v1.6.2-0.20260623130956-98d2c88fce43`).
- The gateway's `graphql-go-tools/v2` pin predates TT-17442, so the
v3/v2 engine path is **not** affected and is intentionally left
unchanged.

- `go mod verify` passes; `internal/graphengine` and
`apidef/adapter/...` build against the new pin.

> Draft — depends on graphql-go-tools#447, which is not merged yet. The
version pin points at the #447 branch commit and must be re-pinned to
the squash-merge commit once #447 lands.

[TT-17442]:
https://tyktech.atlassian.net/browse/TT-17442?atlOrigin=eyJpIjoiNWRkNTljNzYxNjVmNDY3MDlhMDU5Y2ZhYzA5YTRkZjUiLCJwIjoiZ2l0aHViLWNvbS1KU1cifQ

(cherry picked from commit 63316b3)