Curator status/lifecycle ignores skill edit activity

Bug Description

hermes curator status and curator automatic lifecycle transitions still key off last_used_at instead of a unified activity timestamp.

A recent partial fix (#17782) wired skill_view() into bump_use(), so new skill loads now update last_used_at. However, skill_manage() still records maintenance under patch_count / last_patched_at, and historical telemetry may contain last_viewed_at values from before #17782. Curator ignores those activity timestamps when sorting "least recently used" skills and when deciding stale/archive transitions.

The result is that actively maintained skills can appear stale or last_used=never if they were edited/maintained but not loaded through a code path that bumps last_used_at.

Steps to Reproduce

1. Have an agent-created skill in ~/.hermes/skills/.
2. Edit it with skill_manage(action="patch") or otherwise create a record with a recent last_patched_at but no last_used_at.
3. Inspect ~/.hermes/skills/.usage.json and observe that last_patched_at was updated, while last_used_at may still be null.
4. Run:

hermes curator status

Expected Behavior

Curator reporting and lifecycle transitions should treat the latest actual activity timestamp as the most recent of:

• last_used_at
• last_viewed_at
• last_patched_at

A recently viewed or patched skill should not be displayed as last_used=never, nor should it be marked stale/archived solely because last_used_at is unset.

Actual Behavior

Curator status sorts by last_used_at and displays last_used=never for skills that have nonzero view_count or patch_count and recent last_viewed_at / last_patched_at values.

This makes actively maintained skills appear unused and can make curator lifecycle decisions misleading.

Example Evidence

From a local profile before this fix, several skills had recent view/patch activity but use_count=0 and last_used_at=None, including one with view=23, patch=32, and recent last_patched_at. hermes curator status still listed it as last_used=never.

Even after #17782, patch/edit activity remains separate from use activity, so last_patched_at is still not reflected in curator status or lifecycle decisions.

Related Issues

• Related/partial prior fix: Curator: bump_use() has zero production call sites — use_count always 0 #17782 wired skill_view() into bump_use().
• Broader lifecycle tracking umbrella: [Feature]: Skill lifecycle management — usage metadata, staleness, archival, and revalidation #7816.

Proposed Fix

Derive last_activity_at and activity_count in tools.skill_usage.agent_created_report():

• last_activity_at = max(last_used_at, last_viewed_at, last_patched_at)
• activity_count = use_count + view_count + patch_count

Then use last_activity_at for:

• hermes curator status sorting and display
• automatic stale/archive/reactivation transitions
• curator review candidate rendering

Environment

• Repo: NousResearch/hermes-agent
• Observed on current main clone at commit 9a145406
• Python: 3.11
• Platform: macOS