use /flags instead of /decide

[dmarticus]

💡 Motivation and Context

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📝 Checklist

• I reviewed the submitted code.
• I added tests to verify the changes.
• I updated the docs if needed.
• No breaking change or entry added to the changelog.

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- use /flags instead of /decide ([#245](https://github.com/PostHog/posthog-android/pull/245))

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Generated by 🚫 dangerJS against 18f2a64

[marandaneto]

we probably want to rename the json files as well https://github.com/PostHog/posthog-android/tree/main/posthog/src/test/resources/json since they are all called something decide

[marandaneto]

since the response format changes, we need to fix/test this as well

posthog-android/posthog/src/main/java/com/posthog/internal/PostHogRemoteConfig.kt

Line 285 in cfab460

private fun preloadSessionReplayFlag() {

and

posthog-android/posthog/src/main/java/com/posthog/internal/PostHogRemoteConfig.kt

Line 51 in cfab460

private fun isRecordingActive(

ideally in a back compatible way.
js-lite (rn) caused an issue because that wasn't accounted for https://posthog.slack.com/archives/C04MZFDA5KK/p1747734697154639?thread_ts=1746644228.860679&cid=C04MZFDA5KK