fix: Use relative time when viewing logs/events when a node is still running

[yuechao-qin]

Description

Closes https://github.com/Shopify/oasis-frontend/issues/526

When a node is still running, the old code would put hard code start and end time relative to the current time the user views the node. Issues with this is:

• Goes out of sync with latest logs/events
• Didn't work if it's still running, because the end time had a padding of 5 additional minutes into the future (the padding was meant for when a run is completed).

Now, the code does:

• If start time is missing -- Use relative time for the past hour to retrieve logs/events.
• If end time is missing -- Use relative time for the past minutes (plus 5 minute padding) the node has been running to retrieve logs/events.
• If start/end are available -- Use static start/end times with 5 minute padding.

Related Issue and Pull requests

Type of Change

• Bug fix
• New feature
• Improvement
• Cleanup/Refactor
• Breaking change
• Documentation update

Checklist

• I have tested this does not break current pipelines / runs functionality
• I have tested the changes on staging

Test Instructions

• Find a run that a node has not finished
• Click on that node and go to logs panel
• Click on both Observe's logs/events that goes to the site.
  • Confirm the time range is using now with some minutes
  • Confirm running the query doesn't fail

Video

Use cases:

• Node running
• Node ended recently (within 5 minutes of current time)
• Node completed for a while

Screen Recording 2026-03-20 at 3.28.43 PM.mov (uploaded via Graphite)

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[yuechao-qin]

• fix: Use relative time when viewing logs/events when a node is still running #1977 👈 (View in Graphite)
• master

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