test(issue-261): complete Sprint 3 deprecated-path cleanup lane

[graysurf]

Summary

• Complete issue Plan: Workspace obsolete test cleanup and de-risking #261 Sprint 3 lane cleanup for deprecated/removed-path test coverage.
• Remove obsolete parity and fixture artifacts that no longer guard reachable behavior.
• Rebaseline plan-issue-cli help parity checks to assert the current command contract directly.

Scope

• Removed obsolete deprecated-path parity cases from:
  • crates/codex-cli/tests/parity_oracle.rs
  • crates/gemini-cli/tests/parity_oracle.rs
• Reworked crates/plan-issue-cli/tests/parity_guardrails.rs help-surface test to use explicit command-surface assertions.
• Removed stale fixtures:
  • crates/plan-issue-cli/tests/fixtures/shell_parity/help.txt
  • crates/api-test/tests/fixtures/grpc/smoke.suite.json
• Updated shell-parity fixture docs/regenerator:
  • crates/plan-issue-cli/tests/fixtures/shell_parity/README.md
  • crates/plan-issue-cli/tests/fixtures/shell_parity/regenerate.sh
• Produced Sprint 3 classification artifact:
  • /Users/terry/.agents/out/workspace-test-cleanup/deprecated-path-candidates.tsv

Testing

• agent-docs resolve --context startup --strict --format checklist (pass)
• agent-docs resolve --context project-dev --strict --format checklist (pass)
• test -s "$AGENT_HOME/out/workspace-test-cleanup/deprecated-path-candidates.tsv" plus header/field/remove-path checks (pass)
• cargo test -p nils-codex-cli -p nils-gemini-cli -p nils-plan-issue-cli -p nils-api-rest -p nils-api-gql (pass)
• ./.agents/skills/nils-cli-verify-required-checks/scripts/nils-cli-verify-required-checks.sh (pass)
• cargo llvm-cov nextest --profile ci --workspace --lcov --output-path target/coverage/lcov.info --fail-under-lines 85 (not run by request for immediate handoff)

Issue

• Plan: Workspace obsolete test cleanup and de-risking #261

[github-actions]

Coverage

Total line coverage: 86.45% (58994/68243 lines hit).