eventcollector: clean up unused dispatcher timezone code

[lidezhu]

What problem does this PR solve?

Issue Number: close #6335

What is changed and how it works?

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No code

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Summary by CodeRabbit

• Changes
  • Removed timezone information from dispatcher requests and shared dispatcher configuration.
  • Dispatcher registration and reset requests no longer include timezone data.
  • Reserved the former timezone field to prevent reuse in future protocol changes.

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Configuration used: Organization UI

Review profile: CHILL

Plan: Advanced

Run ID: 948bbb4c-4346-484a-bc04-9097ba6d1306

📥 Commits

Reviewing files that changed from the base of the PR and between f2e96bb and 518d246.

⛔ Files ignored due to path filters (1)

• eventpb/event.pb.go is excluded by !**/*.pb.go

📒 Files selected for processing (9)

• downstreamadapter/dispatcher/basic_dispatcher.go
• downstreamadapter/dispatcher/basic_dispatcher_info.go
• downstreamadapter/dispatcher/event_dispatcher_test.go
• downstreamadapter/dispatchermanager/dispatcher_manager.go
• downstreamadapter/dispatchermanager/dispatcher_manager_test.go
• downstreamadapter/eventcollector/dispatcher_session.go
• downstreamadapter/eventcollector/dispatcher_stat_test.go
• downstreamadapter/eventcollector/event_collector_test.go
• eventpb/event.proto

💤 Files with no reviewable changes (8)

• downstreamadapter/dispatchermanager/dispatcher_manager.go
• downstreamadapter/eventcollector/dispatcher_session.go
• downstreamadapter/dispatcher/basic_dispatcher.go
• downstreamadapter/eventcollector/event_collector_test.go
• downstreamadapter/dispatcher/basic_dispatcher_info.go
• downstreamadapter/dispatchermanager/dispatcher_manager_test.go
• downstreamadapter/dispatcher/event_dispatcher_test.go
• downstreamadapter/eventcollector/dispatcher_stat_test.go

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📝 Walkthrough

Walkthrough

The change removes timezone data from dispatcher interfaces, shared state, constructor calls, event registration and reset requests, test doubles, and the DispatcherRequest protobuf field. The protobuf field number and name are reserved.

Changes

Dispatcher timezone removal

Layer / File(s)	Summary
Remove timezone from the event contract eventpb/event.proto	DispatcherRequest no longer contains timezone = 15. Field number 15 and the name timezone are reserved.
Update dispatcher contracts and shared state downstreamadapter/dispatcher/basic_dispatcher.go, downstreamadapter/dispatcher/basic_dispatcher_info.go, downstreamadapter/dispatchermanager/dispatcher_manager.go, downstreamadapter/dispatcher/*_test.go	GetTimezone and the SharedInfo.timezone field are removed. NewSharedInfo and its call sites no longer use a timezone argument.
Stop populating event request timezone downstreamadapter/eventcollector/dispatcher_session.go, downstreamadapter/eventcollector/*_test.go	Register and reset requests no longer set Timezone. Test doubles no longer implement GetTimezone.

Priority: ⬇️ Low

Estimated code review effort: 2 (Simple) | ~10 minutes

Change: Refactor

Suggested reviewers: asddongmen

Merge Risk: ⚪ Minimal · up to 518d2

The cleanup removes unused dispatcher timezone data without changing the remaining request fields, and preserves the protobuf field reservation. No production impact is identified.

🚥 Pre-merge checks | ✅ 4 | ❌ 1

❌ Failed checks (1 warning)

Check name	Status	Explanation	Resolution
Description check	⚠️ Warning	The description includes the issue reference, but the change summary, test selection or results, compatibility answers, documentation assessment, and release note are incomplete.	Describe what changed and how it works. Select and document the applicable test type and results. Answer both questions about compatibility and documentation. Add a release note or state None.

✅ Passed checks (4 passed)

Check name	Status	Explanation
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check. Docstring coverage is scoped to functions touched by this diff. Analyzed 0 functions across 0…
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Title check	✅ Passed	The title clearly and concisely describes the main change: removal of unused dispatcher timezone code from the event collector.

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_{A rabbit hops where timezones flew
The dispatcher sheds one field from view
Shared state grows slightly lean
Requests carry no timezone sheen
Reserved numbers guard the trail
Clean contracts now prevail}

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