obs: agent field records full file path instead of short name for some invocations

[agents-squads]

Problem

11/57 observability records have the agent field as a full absolute path instead of the short agent name.

Examples:

/Users/jorgevidaurre/agents-squads/hq/.agents/squads/cli/cli-lead.md
/Users/jorgevidaurre/agents-squads/hq/.agents/squads/company/company-lead.md
/Users/jorgevidaurre/agents-squads/hq/.agents/squads/engineering/eng-lead.md

Expected:

cli-lead
company-lead
eng-lead

All 11 affected records are from 2026-03-27T16:07 (a batch run using full file paths). Later runs from the same day correctly use short names, suggesting this was a regression in how agents were invoked in that batch.

Impact

• Analytics queries on agent field break (can't group by agent name)
• Cost-per-agent reports are inconsistent
• 11 records cannot be filtered by squad or agent name correctly

Fix

When recording the agent field in executions.jsonl, strip to basename without extension if the value is a file path.

source:data

[agents-squads]

Fixed by PR #668 (merged). The obs normalization code in agent-runner.ts now strips the full path to short name for all invocations.