refactor(time): reduce internal date conversions PR 6 [WPB-10090]

[MohamadJaara]

https://wearezeta.atlassian.net/browse/WPB-10090

Small cleanup to keep a few more timestamps typed as Instant internally and avoid repeated formatting/parsing.

• uses Instant for conversation status refs, server time, and subconversation epoch time
• formats reaction timestamps once
• removes the unused Android DateTimeFormatter path

No DB migration is needed. Callers passing a custom conversation status timestamp should now pass an Instant.

Stacked on #4338.

Checks: Logic and Persistence JVM tests, Detekt, ABI check, and the Android core:util compile.

[github-actions]

Test Results

0 tests  ±0   0 ✅ ±0   0s ⏱️ ±0s
0 suites ±0   0 💤 ±0 
0 files   ±0   0 ❌ ±0 

Results for commit f0abeb4. ± Comparison against base commit fa069a5.

♻️ This comment has been updated with latest results.

[codecov-commenter]

Codecov Report

❌ Patch coverage is 76.47059% with 8 lines in your changes missing coverage. Please review.
✅ Project coverage is 61.23%. Comparing base (fa069a5) to head (f0abeb4).

Files with missing lines	Patch %	Lines
...in/com/wire/kalium/logic/data/event/EventMapper.kt	16.66%	1 Missing and 4 partials ⚠️
...ersistence/dao/conversation/ConversationDAOImpl.kt	50.00%	1 Missing ⚠️
...ic/data/conversation/JoinSubconversationUseCase.kt	92.85%	0 Missing and 1 partial ⚠️
...rsation/UpdateConversationArchivedStatusUseCase.kt	0.00%	1 Missing ⚠️

Additional details and impacted files

@@              Coverage Diff              @@
##             develop    #4339      +/-   ##
=============================================
+ Coverage      61.11%   61.23%   +0.11%     
- Complexity      4238     4244       +6     
=============================================
  Files           2200     2200              
  Lines          78411    71550    -6861     
  Branches        7223     7225       +2     
=============================================
- Hits           47920    43811    -4109     
+ Misses         27638    24877    -2761     
- Partials        2853     2862       +9     

Files with missing lines	Coverage Δ
.../kalium/logic/data/conversation/SubConversation.kt	66.66% <100.00%> (ø)
...um/persistence/dao/conversation/ConversationDAO.kt	86.20% <ø> (ø)
...ire/kalium/persistence/dao/reaction/ReactionDAO.kt	62.50% <100.00%> (ø)
.../com/wire/kalium/logic/data/call/CallRepository.kt	89.66% <100.00%> (+0.44%)	⬆️
.../logic/data/conversation/ConversationRepository.kt	53.10% <ø> (+0.68%)	⬆️
...ogic/data/conversation/ConversationStatusMapper.kt	59.09% <ø> (-1.78%)	⬇️
...m/logic/data/conversation/SubConversationMapper.kt	66.66% <100.00%> (+66.66%)	⬆️
...n/kotlin/com/wire/kalium/logic/data/event/Event.kt	75.52% <100.00%> (+1.31%)	⬆️
...nversation/UpdateConversationMutedStatusUseCase.kt	94.11% <100.00%> (ø)
.../receiver/conversation/MemberChangeEventHandler.kt	94.73% <100.00%> (-0.51%)	⬇️
... and 4 more

... and 1098 files with indirect coverage changes

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[github-actions]

Bencher Report

Branch	${GITHUB_HEAD_REF}
Testbed	ubuntu-latest

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Benchmark	Latency	microseconds (µs)
com.wire.kalium.benchmarks.logic.CoreLogicBenchmark.createObjectInFiles	📈 view plot ⚠️ NO THRESHOLD	909.54 µs
com.wire.kalium.benchmarks.logic.CoreLogicBenchmark.createObjectInMemory	📈 view plot ⚠️ NO THRESHOLD	573,543.50 µs
com.wire.kalium.benchmarks.persistence.MessageReadBenchmark.inboxPagingDeepPageBenchmark	📈 view plot ⚠️ NO THRESHOLD	134,891.54 µs
com.wire.kalium.benchmarks.persistence.MessageReadBenchmark.inboxPagingFirstPageBenchmark	📈 view plot ⚠️ NO THRESHOLD	129,762.62 µs
com.wire.kalium.benchmarks.persistence.MessageReadBenchmark.localMarkAsReadBenchmark	📈 view plot ⚠️ NO THRESHOLD	3,474.96 µs
com.wire.kalium.benchmarks.persistence.MessageReadBenchmark.messagePagingDeepPageBenchmark	📈 view plot ⚠️ NO THRESHOLD	28,158.36 µs
com.wire.kalium.benchmarks.persistence.MessageReadBenchmark.messagePagingFirstPageBenchmark	📈 view plot ⚠️ NO THRESHOLD	13,287.50 µs
com.wire.kalium.benchmarks.persistence.MessagesNoPragmaTuneBenchmark.messageInsertionBenchmark	📈 view plot ⚠️ NO THRESHOLD	1,372,380.30 µs
com.wire.kalium.benchmarks.persistence.MessagesNoPragmaTuneBenchmark.queryMessagesBenchmark	📈 view plot ⚠️ NO THRESHOLD	21,512.23 µs

🐰 View full continuous benchmarking report in Bencher