add "kc" and "kac" to ignore params

[ladamski]

https://app.asana.com/1/137249556945/project/1209805270658160/task/1214934152266987?focus=true

Looks like it can occasionally occur for non-Windows pixels (which makes sense if via proxy injection)

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Note

Low Risk
Config-only additions to ignore_params.json with no runtime logic changes; only affects which URL params pass pixel definition validation.

Overview
Extends the global pixel ignore params list so validation no longer treats kc and kac as unknown query parameters when third-party SERP proxies inject them (same treatment as existing kp / p entries, with allowed value -1).

This should reduce false validation noise on non-Windows pixels when those params appear in URLs.

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