[Drilldowns] Improve URL Drilldown experience for table visualizations

[Dosant]

Describe the feature:

This is an umbrella issue for drilldowns experience in Saved Search and table visualisations panels.
Currently drilldowns are not supported in Saved Search panels and have limited support in table visualization.

Describe a specific use case for the feature:

Issue specific to Saved Search panels: #73283 described the use case in details. Tables visualisations have similar use case.
We should consider this use-case: #73283 (comment)

Challenges

For #73283 (comment) we probably should make triggers more dynamic and generate those from table columns. See technical details here: #76226

Part of: #42845

[elasticmachine]

Pinging @elastic/kibana-app-arch (Team:AppArch)

[Dosant]

For reference:

1. Note from @elastic-jb about limitation that it is impossible to Drilldown on aggregated value on a table now: [Drilldows] Url Drilldown basic template helpers #80500 (comment)
2. Quick POC with exposing event.row which at least gives access to the whole row. But it is still impossible to click on aggregated value: [discuss][Drilldowns][URL drilldown] Expose "event.row" in VALUE_CLICK_TRIGGER #79157

[streamich]

• Row click trigger.
• Option in URL config UI to select column.
• Helper for being able to pick columns in template editor conditional.

[Dosant]

• New trigger: row trigger
  • use dummy values approach for preview
  • give event.columns array probably
• Ability to value click on aggregated value
• Use new conditional helpers + weaken the validation to be able to attach a drilldown to specific column
• POC column picker inside drilldown editor

[Dosant]

4 different tables:

[streamich]

[streamich]

Variables for row trigger:

{{event.rowIndex}}
{{event.values.[0]}}
{{event.keys.[0]}} - fallback to column name on missing (check if VALUE_CLICK has it, add)
{{event.columnNames.[0]}} - if easy

[streamich]

Template:

{{event.values}}

Preview:

NO PREVIEW FOR NOW
{{event.values}}
column-1,column-2,column-3,...
Real name 1, Real name 2, Real name 3,...