feature/persist technique tags

[patriciapampanelli]

Summary

• Persist ordered demon:* probe technique tags on every attempt row as technique_tags.
• Emit eval_technique aggregate rows mirroring the existing eval_intent report pattern.
• Preserve technique_tags: [] as a first-class state for probes without technique tags.
• Preserve T&I metadata when buffs derive new attempts.

Test plan

• python3 -m pytest tests/test_attempt.py::test_json_serialize tests/test_attempt.py::test_attempt_technique_tags_serialize_and_copy tests/test_internal_structures.py -k "technique_tags or eval_technique" -v
• python3 -m pytest tests/test_attempt.py tests/langservice/probes/test_probes_base.py tests/test_internal_structures.py -v

Notes

• Resolves feature: persist technique tags per-attempt in report.jsonl #1703
• Depends on cas: add technique tags to existing probes #1691
• Legacy reports are not migrated: missing technique_tags means a pre-change report, while technique_tags: [] means a new report where the probe had no demon:* technique tag.
• Out of scope: report digest / HTML changes for reporting: propagate intent & technique to report digest #1704.

[jmartin-tech]

Per separate discussion, since tags are part of probes and the probe is already referenced by the attempt, this can be refactored to read these values from the plugin cache and should likely inject a copy of the plugin metadata into the report.jsonl for use in reprocessing digests.

This avoids duplications in the attempts and also provides for easier maintenance and detection of comparability for runs.

[patriciapampanelli]

Per separate discussion, since tags are part of probes and the probe is already referenced by the attempt, this can be refactored to read these values from the plugin cache and should likely inject a copy of the plugin metadata into the report.jsonl for use in reprocessing digests.

This avoids duplications in the attempts and also provides for easier maintenance and detection of comparability for runs.

Updated this to stop persisting technique_tags on each Attempt. The eval_technique aggregate now resolves demon:* probe tags via PluginCache.plugin_info(probe_classpath) at evaluator time, using the existing probe identity carried by the attempt.

This keeps plugin metadata in the cache as the source of truth. When #1720 adds the persisted plugin cache header to report.jsonl, this lookup remains the single place to adapt without reintroducing per-attempt metadata.