fix: Multiple attachments support for feedback

[tustanivsky]

📜 Description

Updated SentryFeedback to accept [Attachment] objects instead of raw [Data] arrays, enabling proper support for
multiple attachments with full metadata (filename, content type, etc.).

This also introduces some breaking changes to public API:

• init method signature
• dataDictionary() method now returns attachments as [[String: Any]] with metadata instead of [Data] affecting consumers of the onSubmitSuccess callback

This issue originally came up in Unreal SDK while adding attachment support for user feedback:

• Add attachments support for user feedback sentry-unreal#1121

💡 Motivation and Context

The previous implementation had several limitations:

1. Hardcoded metadata: attachmentsForEnvelope() assumed all attachments were screenshots and hardcoded filename: "screenshot.png" and contentType: "application/png"
2. Single attachment limitation: Only the first attachment was processed despite accepting an array
3. Lost metadata: Converting Attachment → Data → Attachment discarded important information like custom filenames and content types
4. Backend supports multiple: The Sentry backend can successfully process and display multiple feedback attachments, but the SDK wasn't taking advantage of this

💚 How did you test it?

• Added/updated tests
• Manually using Unreal SDK sample project.

📝 Checklist

You have to check all boxes before merging:

• 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.

Closes #6753

[codecov]

Codecov Report

❌ Patch coverage is 13.33333% with 13 lines in your changes missing coverage. Please review.
⚠️ Please upload report for BASE (main@8447671). Learn more about missing BASE report.
⚠️ Report is 4 commits behind head on main.
✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
...ift/Integrations/UserFeedback/SentryFeedback.swift	16.666%	10 Missing ⚠️
...UserFeedback/SentryUserFeedbackFormViewModel.swift	0.000%	3 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff            @@
##             main     #6752   +/-   ##
========================================
  Coverage        ?   85.613%           
========================================
  Files           ?       453           
  Lines           ?     27692           
  Branches        ?     12147           
========================================
  Hits            ?     23708           
  Misses          ?      3939           
  Partials        ?        45           

Files with missing lines	Coverage Δ
...UserFeedback/SentryUserFeedbackFormViewModel.swift	84.384% <0.000%> (ø)
...ift/Integrations/UserFeedback/SentryFeedback.swift	59.183% <16.666%> (ø)

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[github-actions]

Performance metrics 🚀

	Plain	With Sentry	Diff
Startup time	1230.00 ms	1262.05 ms	32.05 ms
Size	24.14 KiB	1.01 MiB	1011.55 KiB

Baseline results on branch: main

Startup times

Revision	Plain	With Sentry	Diff
ad964ca	1234.73 ms	1254.88 ms	20.15 ms
e16fd46	1228.64 ms	1251.57 ms	22.93 ms
c8dd5e4	1217.67 ms	1242.90 ms	25.23 ms
6d0b605	1218.58 ms	1251.06 ms	32.48 ms
f747c9c	1237.90 ms	1264.77 ms	26.87 ms
2691350	1224.92 ms	1255.82 ms	30.90 ms
fc05805	1220.63 ms	1252.16 ms	31.54 ms
d83b35a	1212.48 ms	1237.02 ms	24.54 ms
d157d83	1228.02 ms	1252.47 ms	24.45 ms
1fecbb8	1242.78 ms	1265.40 ms	22.62 ms

App size

Revision	Plain	With Sentry	Diff
ad964ca	23.75 KiB	913.17 KiB	889.42 KiB
e16fd46	23.74 KiB	1.01 MiB	1008.95 KiB
c8dd5e4	23.75 KiB	913.48 KiB	889.72 KiB
6d0b605	23.75 KiB	1023.82 KiB	1000.07 KiB
f747c9c	23.75 KiB	995.60 KiB	971.85 KiB
2691350	23.75 KiB	850.73 KiB	826.98 KiB
fc05805	23.75 KiB	908.02 KiB	884.27 KiB
d83b35a	23.75 KiB	913.17 KiB	889.42 KiB
d157d83	23.75 KiB	928.85 KiB	905.10 KiB
1fecbb8	23.75 KiB	969.28 KiB	945.53 KiB

Previous results on branch: fix/feedback-attachments

Startup times

Revision	Plain	With Sentry	Diff
458b1de	1234.70 ms	1270.40 ms	35.70 ms
982084f	1222.33 ms	1250.73 ms	28.40 ms

App size

Revision	Plain	With Sentry	Diff
458b1de	24.14 KiB	1.01 MiB	1015.55 KiB
982084f	24.14 KiB	1.01 MiB	1015.55 KiB

[itaybre]

lgtm

[philprime]

LGTM