UI: Preserve raw connection extra JSON

[Vamsi-klu]

Problem

Editing a Snowflake connection in the UI could silently rewrite the raw extra JSON. If the connection had manually entered extras such as {"account":"1234"}, opening and saving the form could replace that JSON with provider-field defaults like {"insecure_mode":false}.

closes: #57984

What Changed

The connection form now preserves the raw extra JSON as the source of truth for keys that the user did not change through provider-specific fields.

Provider extra fields are initialized from matching keys in the raw JSON, but untouched provider defaults are not serialized back into the JSON. When a user edits a provider field, only that changed key is merged into the existing JSON. Clearing a provider field removes that key while preserving unrelated keys.

Impact

Users can safely edit Snowflake connections without losing manually configured extras. Existing raw JSON keys are preserved, and defaults such as insecure_mode: false are not injected unless the user explicitly changes the field.

Testing

• pnpm exec vitest run src/queries/useParamStore.test.ts src/pages/Connections/ConnectionForm.test.tsx
• pnpm lint
• Commit hook: Compile / format / lint UI
• git diff --check

The tests cover the problem statement expectations: preserving account, avoiding untouched insecure_mode, preserving unknown keys, merging changed provider fields, and removing cleared provider fields.

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• Yes — Codex (GPT-5)

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