Add os_version to active subscription pixel

[karlenDimla]

Task/Issue URL: https://app.asana.com/1/137249556945/project/488551667048375/task/1212426814527389?focus=true

Description

Added os_version and petal to the pixel.
Removed atb from the pixel.
Added entry for pixel registry.
https://app.asana.com/1/137249556945/project/69071770703008/task/1212452022245359?focus=true

Steps to test this PR

QA-optional

---

Note

Adds os_version and petal to m_privacy-pro_app_subscription_active and stops including ATB for it, with registry entry and sender wiring.

• Pixels:
  • Active subscription (m_privacy-pro_app_subscription_active):
    • Add parameters os_version (from AppBuildConfig.sdkInt) and petal (hardcoded "true").
    • Stop including ATB; keep APP_VERSION only in includedParameters.
  • Register pixel in PixelDefinitions/pixels/subscription_pixels.json5 with new params.
• Implementation:
  • Update SubscriptionPixelSender.reportSubscriptionActive to send os_version and petal.
  • Add SubscriptionPixelParameter.OS_VERSION and PETAL constants.

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[karlenDimla]

• Add os_version to active subscription pixel #7406 👈 (View in Graphite)
• develop

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[lmac012]

LGTM, just a couple of comments.

[lmac012]

This is always fired as a "daily" pixel, and as such, it has the _d suffix. This is not accounted for in this definition and will most likely cause validation errors. You could add "daily_count_short" to "suffixes", but this is never fired as a "count" type of pixel, so it's probably better to just include the type suffix in the name:

Suggested change

	"m_privacy-pro_app_subscription_active": {
	"m_privacy-pro_app_subscription_active_d": {

[lmac012]

I'm not sure about the best practices here, but shouldn't we add "enum": ["true"] to indicate that this is the only possible value for the petal param? cc @nshuba

Regardless, I think it would make sense to add this parameter to params_dictionary.json, since it's not specific to this pixel and will likely get reused on other pixels as well.