fix(anr): Detect main thread from tombstone via pid matching thread id

[markushi]

📜 Description

Analogous to the ANR thread-dump fix in #5733, applied it to the tombstone (ApplicationExitInfo native crash) path as well.

Changes

• Mark the tombstone thread whose id equals the process id as the main thread and set its name to "main".

No public API change.

💡 Motivation and Context

When the OS names the main thread after the process (or leaves it unnamed), native crashes were not attributed to the main thread. Matching on id == pid is robust and does not depend on the (truncatable) process name.

💚 How did you test it?

• Added a unit test to TombstoneParserTest covering main-thread detection and name normalization, with separate crashed/background threads to verify independence.
• Strengthened the existing snapshot test to assert the main thread is detected from real tombstone data.

📝 Checklist

• I added GH Issue ID & Linear ID
• I added tests to verify the changes.
• No new PII added or SDK only sends newly added PII if sendDefaultPII is enabled.
• I updated the docs if needed.
• I updated the wizard if needed.
• Review from the native team if needed.
• No breaking change or entry added to the changelog.
• No breaking change for hybrid SDKs or communicated to hybrid SDKs.

🔮 Next steps

[sentry]

📲 Install Builds

Android

🔗 App Name	App ID	Version	Configuration
SDK Size	io.sentry.tests.size	8.48.0 (1)	release

⚙️ sentry-android Build Distribution Settings

[github-actions]

Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	318.53 ms	402.32 ms	83.79 ms
Size	0 B	0 B	0 B

Baseline results on branch: main

Startup times

Revision	Plain	With Sentry	Diff
bbc35bb	324.88 ms	425.73 ms	100.85 ms
abfcc92	304.04 ms	370.33 ms	66.29 ms
94bff8d	313.23 ms	352.77 ms	39.54 ms
fcec2f2	311.35 ms	384.94 ms	73.59 ms
d15471f	304.55 ms	408.43 ms	103.87 ms
4c04bb8	307.93 ms	362.34 ms	54.41 ms
b936425	302.69 ms	372.86 ms	70.17 ms
d501a7e	314.55 ms	343.34 ms	28.79 ms
72020f8	312.32 ms	370.94 ms	58.62 ms
6b019b7	319.84 ms	333.15 ms	13.31 ms

App size

Revision	Plain	With Sentry	Diff
bbc35bb	1.58 MiB	2.12 MiB	553.01 KiB
abfcc92	1.58 MiB	2.13 MiB	557.31 KiB
94bff8d	1.58 MiB	2.20 MiB	635.37 KiB
fcec2f2	1.58 MiB	2.12 MiB	551.51 KiB
d15471f	1.58 MiB	2.13 MiB	559.54 KiB
4c04bb8	0 B	0 B	0 B
b936425	0 B	0 B	0 B
d501a7e	0 B	0 B	0 B
72020f8	1.58 MiB	2.19 MiB	620.21 KiB
6b019b7	0 B	0 B	0 B

Previous results on branch: fix/anr-tombstone-main-thread-detection

Startup times

Revision	Plain	With Sentry	Diff
81a3256	450.06 ms	581.68 ms	131.62 ms
2e04adf	314.06 ms	365.72 ms	51.66 ms

App size

Revision	Plain	With Sentry	Diff
81a3256	0 B	0 B	0 B
2e04adf	0 B	0 B	0 B