fix(plugin-firebase): show runnable examples instead of {...}

[datlechin]

Why

macOS Tests has failed on main since #3392. Two Firebase error messages used {...} as a placeholder in a JSON example, and EllipsisConventionTests refuses three periods in any live catalog string. The placeholder also left the user with an example they could not paste: {...} is not valid JSON.

Change

• The raw filter refusal now shows a complete Filter object, {"unaryFilter": {"field": {"fieldPath": "email"}, "op": "IS_NULL"}}.
• The request syntax message now shows a complete QUERY, QUERY {"structuredQuery": {"from": [{"collectionId": "users"}]}}.
• Both examples moved out of the localized keys into %@ arguments, so a translator never edits JSON and a test runs each one. The two old keys had no translations.

Verified

EllipsisConventionTests fails on main with these two keys and finds no offender here. Two new package tests parse every example each message gives.