Auto Reconcile Retained Size Projection

1. Spec

• 1.1 Add an OpenSpec change for bounded retained-size auto-reconcile and owner-safe stale copy.
• 1.2 Validate the change with strict OpenSpec checks.

2. Implementation

• 2.1 Invoke retained-size reconcile automatically on stale/failed retained-size dataset summary reads.
• 2.2 Add an in-process cooldown after read-path reconcile failure.
• 2.3 Preserve stale/failed projection metadata when reconcile fails.
• 2.4 Replace dashboard stale/failure hero body text with concise owner-safe copy.

3. Regression Tests

• 3.1 Cover global-only dirty retained-size metadata with clean stream/connection rows.
• 3.2 Cover dirty row reconcile success from the dataset summary read.
• 3.3 Cover reconcile failure returning stale/failed metadata and not retrying on the immediate next read.
• 3.4 Cover dashboard copy excluding raw internal reasons.

4. Acceptance Checks

• 4.1 Run targeted retained-size and route tests.
• 4.2 Run targeted standing dashboard view-model tests.
• 4.3 Run openspec validate auto-reconcile-retained-size-projection --strict.