MTTD Support and Detection Overview Dashboard

**What the feature is (as Title)**
MTTD Support and Detection Overview Dashboard

**Value proposition**
As Security Operations teams use multiple detection rule types (KQL, Lucene, EQL, and ES|QL), there is a need to consistently calculate and visualize Mean Time to Detect (MTTD) across all rule types.

Currently, MTTD calculation depends on fields such as:
- kibana.alert.original_time
- kibana.alert.original_event.ingested
- kibana.alert.start

However, it is unclear whether these fields are consistently available across all rule types, especially ES|QL-based detection rules.

This creates challenges in building a unified dashboard and measuring detection performance accurately.

**Expected outcome**
- Ability to calculate MTTD for all rule types:
- KQL
- Lucene
- EQL
- ES|QL

- Consistent population of required timestamp fields across all alerts
- Support for ES|QL-based rules in MTTD calculations without limitations
- Ability to build a unified Detection Overview Dashboard including all rule types
- Accurate tracking of detection performance (MTTD) across different detection strategies

**use cases**
To measure MTTD across all detection rules so that I can evaluate detection performance consistently
A single dashboard that includes all rule types so that I can track KPIs like MTTD and MTTR
To ensure ES|QL rules are included in performance metrics so that I can compare them with other rule types
To identify delays in detection (ingestion vs rule execution) across all rule types