Replace ANR profiling boolean flag with sample-rate

[markushi]

📜 Description

Replaces the boolean flag with a sample-rate.

#skip-changelog

[github-actions]

Semver Impact of This PR

⚪ None (no version bump detected)

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[sentry]

Bug: Unsampled ANR events are incorrectly fingerprinted as "system-frames-only-anr" because the check isAnrProfilingEnabled() doesn't confirm if the specific event was actually profiled.
_{Severity: MEDIUM}

Suggested Fix

The setDefaultAnrFingerprint() method should only apply the "system-frames-only-anr" fingerprint if the ANR event was actually profiled. This can be achieved by having applyAnrProfile() set a flag on the event to indicate a profile was applied. The fingerprinting logic should then check this flag instead of relying on the general isAnrProfilingEnabled() setting.

Prompt for AI Agent

Review the code at the location below. A potential bug has been identified by an AI
agent.
Verify if this is a real issue. If it is, propose a fix; if not, explain why it's not
valid.

Location:
sentry-android-core/src/main/java/io/sentry/android/core/ApplicationExitInfoEventProcessor.java#L737

Potential issue: When ANR profiling is enabled with a sample rate less than 1.0, ANR
events that are not sampled are incorrectly fingerprinted. The logic in
`setDefaultAnrFingerprint` checks if profiling is enabled via `isAnrProfilingEnabled()`,
but does not check if the specific ANR event was actually profiled. If an unsampled ANR
event happens to only contain system frames, it will be assigned the
`"system-frames-only-anr"` fingerprint. This fingerprint is intended for cases where
profiling was performed but found no application frames, leading to incorrect issue
grouping in Sentry for unsampled ANRs.

_{Did we get this right? 👍 / 👎 to inform future reviews.}

[github-actions]

Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	337.96 ms	412.98 ms	75.02 ms
Size	1.58 MiB	2.29 MiB	728.81 KiB

Baseline results on branch: markushi/feat/anr-profiling

Startup times

Revision	Plain	With Sentry	Diff
83a9ec4	333.84 ms	390.30 ms	56.47 ms
00299fd	359.87 ms	424.85 ms	64.98 ms
eb02e45	362.67 ms	431.71 ms	69.04 ms
edecf31	310.80 ms	367.02 ms	56.22 ms
8c4e7d6	309.15 ms	359.27 ms	50.12 ms
8d7c3bb	304.55 ms	377.88 ms	73.33 ms
4c0ffee	314.94 ms	377.79 ms	62.86 ms
ddbbe91	289.51 ms	359.74 ms	70.23 ms
fca8df8	326.79 ms	379.69 ms	52.90 ms
c10e603	367.92 ms	393.50 ms	25.58 ms

App size

Revision	Plain	With Sentry	Diff
83a9ec4	1.58 MiB	2.29 MiB	723.99 KiB
00299fd	1.58 MiB	2.29 MiB	723.50 KiB
eb02e45	1.58 MiB	2.29 MiB	725.26 KiB
edecf31	1.58 MiB	2.29 MiB	726.95 KiB
8c4e7d6	1.58 MiB	2.29 MiB	727.03 KiB
8d7c3bb	1.58 MiB	2.29 MiB	727.01 KiB
4c0ffee	1.58 MiB	2.29 MiB	723.67 KiB
ddbbe91	1.58 MiB	2.29 MiB	724.15 KiB
fca8df8	1.58 MiB	2.29 MiB	723.68 KiB
c10e603	1.58 MiB	2.29 MiB	723.72 KiB