[Story]: Ingestion run history (PM view)

[adoLime]

User Story

As a PM, I want to view the history of past ingestion runs (when they ran, per source, with counts of ingested / updated / failed artifacts), so that I can monitor ingestion health and trace when content entered the system.

Context & Motivation

• Type: Functional
• Parent epic: 03 EPIC - Connectors & Artifact Ingestion #52
• Teams: team:backend (endpoint), team:frontend (PM view)

Acceptance Criteria

• Given ingestion runs exist, when a PM calls the ingestion-runs endpoint, then it returns recent runs (most recent first) with: run_id, source_system, started_at, finished_at, counts ingested / updated / failed.
• For v0, the endpoint returns a sensible recent window (simple limit or pagination — exact size decided in refinement; no hard requirement on the number).
• Admin view in the frontend renders this list (read-only).

Dependencies

• Depends on: [Story]: Canonical artifact schema and metadata normalization #161 (Canonical artifact schema — defines the ingestion_run table and provenance fields).
• Related: [Story]: Ingestion status view #101 (Ingestion status view), [Story]: Dashboard with ingestion status #121 (Dashboard with ingestion status), [Story]: GitHub repository connector v0 (commits, files, issues, PR metadata) #159 / [Story]: Jira CSV issue connector adapter #160 (connectors produce the run records).