Single field update log UI

[karilint]

Currently, there is an Update tab for each entity locality/species/etc.

Sometimes the user wants to see updates for a single field:

• value before and after
• who made the update and when
• what reference was used for the update

The updates should be visible by hovering over the field or using a symbol near the field, which shows the update history for the field.

[karilint]

Starting implementation for a shared single-field update history UI. The coding task is to reuse the existing update log data already loaded for detail pages and expose field-specific history from read-mode fields, preferably through a small icon/popover near field labels so locality/species/time-unit/time-bound screens can share the behavior.

[karilint]

Implemented in draft PR #1190: the existing update-log data was already available inside detail payloads, but read-mode field labels had no field-specific entry point to it. The change adds a small history icon next to labels whose field name matches an update log column, opening a popover with date/editor/coordinator/action, before/after values, comment, and references.

[karilint]

Manual test checklist for draft PR #1190:

• Open a detail page with existing update rows for a visible field.
• Confirm the history icon appears next to labels whose field name matches an update log column.
• Open the icon and verify date, editor, coordinator, action, before/after values, comment, and references are shown when available.
• Confirm fields without matching update rows do not show the history icon.
• Switch to edit/new/staging mode and confirm the field history icon is not shown in non-read modes.