[ROSETTA] Reject duplicate Curiocity agent IDs

[isolomatov-gd]

In src/curiocity/src/config/schema.ts, a case can repeat an agent ID, causing the matrix builder to emit duplicate trial coordinates that run concurrently and target the same artifact directory. Enforce unique agent IDs at the case-config boundary and add file-based and inline configuration tests.

[github-actions]

Rosetta Triage

Classification: bug, duplicate case agent IDs produce duplicate trial identities.
Priority assessment: Medium. A malformed case can run concurrent trials against the same result directory and overwrite evidence.

Findings:

• caseConfigSchema accepts repeated values in agents.
• The matrix emits one cell per listed ID; trial artifacts are stored by case, agent, and repeat, so duplicate IDs collide.
• The CLI agent option filters the declared IDs through a set; it cannot introduce this duplication.

Suggestions:

• Enforce uniqueness directly on the non-empty agents array, with an error that identifies the duplicate-ID rule.
• Add an inline schema test and a config.json fixture validated through case discovery or validateCase; assert the file path reports an invalid agents field.

Next steps: Implement the boundary validation and the two regression tests.

Automated triage by Rosetta agent