Use dictionary instead of switch statement

[erneestoc]

Why

• Performance: Dictionary hash lookup is O(1) vs O(n) linear scan through switch cases. This function is called for every object in every GraphQL response during JSON deserialization.
• Scales with schema size: The switch becomes increasingly expensive as schemas grow. Our production schema has ~4,200 types.
• No behavioral change: The function signature, return type, and semantics are identical — returns the matching Object or nil.

[apollo-cla]

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[github-actions]

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