refactor(talents): remove agent.* chronicle read-shim
The talents-rename lode (commit 0050be8c) left a read-side shim
accepting legacy agent.* chronicle event names through a stated
2026-05-01 sunset. That sunset assumed chronicle JSONL would be
purged by think/retention.py before the cutoff — not true.
Chronicle events are retained indefinitely, so the shim would
have lived forever as-is. Removing it now as a clean break
rather than carrying dead code.
think/pipeline_health.py and apps/home/routes.py drop the
dual-value set-membership checks against {"agent.X", "talent.X"}
in favor of single-value == comparisons on talent.* — idiomatic
with the surrounding branches in each file.
scripts/gate_agents_rename.py drops its SHIM_FILES / SHIM_WINDOW
suppression for those two files; iter_lines() collapses to a
plain enumerate. The gate now scans them as ordinary production
code with zero new allowlist entries.
Three tests that existed solely to enforce the shim (and whose
names announced as much) are deleted:
- test_newsletter_attempts_accept_legacy_agent_fail
- test_failure_reader_accepts_legacy_and_new_names
- test_reader_accepts_legacy_and_new_event_names
Pre-rename agent.* chronicle events on disk become ignored —
acceptable per founder decision.
Co-authored-by: Codex <codex@openai.com>