chore: updates apollo-client and graphql to latest

[v3nant]

Summary

• Bumps @apollo/client from ^4.1.9 → ^4.2.3
• Bumps graphql from ^16.13.2 → ^17.0.0 (Apollo 4.2.x declares support for both ^16 and ^17)
• Adds module augmentations to apollo.client.ts to satisfy Apollo 4.2.x's new type-safety requirements

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Why the type augmentations are needed

Apollo Client 4.2 introduced two breaking type-system changes:

1. DeclareDefaultOptions — required before using errorPolicy as a default

Apollo 4.2 uses a type-guard pattern that makes errorPolicy in defaultOptions resolve to an error-message string type unless explicitly declared via module augmentation. Without this, the createApollo factory produced a TS2322 error.

2. SignatureStyle — modern vs. classic call signatures

Declaring non-empty DeclareDefaultOptions interfaces causes Apollo to automatically switch client.mutate and client.query to the new "modern" signature style, which:

• Requires TypedDocumentNode and type inference
• Does not accept explicit <TData, TVariables> type arguments

Since all existing call sites use explicit generics against plain DocumentNode, we pin signatureStyle: 'classic' in TypeOverrides to preserve backward-compatible behavior.

Future work: migrating to the modern signature style involves typing each gql document as TypedDocumentNode<ResponseType, VariablesType> and removing explicit generic arguments from all client.mutate/client.query call sites. The five documents in gql-operations.ts are the starting point.

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Test plan

• npm run typecheck passes with zero errors
• npm test passes
• Manual smoke test: hd scan completes successfully