bug(harness): AllEventTypes() omits the three plan.approval_* events that plan_mode emits

[dennisonbertram]

Work type

Bug / regression

Observed behavior

AllEventTypes() in internal/harness/events.go:392 omits plan.approval_required, plan.approval_granted, and plan.approval_denied, which plan_mode.go emits (verified live: a plan-mode run streams all three). Anything that treats AllEventTypes() as the canonical list (event catalog generation, schema validation, TUI/macapp event allowlists if any) misses them. Found while regenerating docs/design/event-catalog.md for #1379.

Expected behavior

AllEventTypes() returns every EventType constant; a test enforces that the list and the constants stay in sync.

Reproduction

awk '/func AllEventTypes/,/^}/' internal/harness/events.go | grep -c PlanApproval → 0; grep -c EventPlanApproval internal/harness/events.go → 3.

User and operational impact

Consumers relying on the list silently drop three plan-mode events; documentation generated from it is incomplete.

Suspected seam and search evidence

internal/harness/events.go list vs constants; searched callers of AllEventTypes (rg AllEventTypes).

Blast-radius impact map

Callers of AllEventTypes only; no wire change. Tests: add a reflection/parse-based sync test in internal/harness.

Regression test first

Named below per item; red command go test <pkg> -run <Test>.

Fix boundaries

In scope: the single seam named. Out of scope: any wire or schema change.

Diagnostic and observability evidence

Grep evidence cited above.

Verification plan

Red/green; go test <pkg> -race; full regression script.

Rollout and rollback

None — no persisted or deployed behavior changes beyond populating an existing column / list; revert PR.

Documentation and handoff

Engineering log entry.

Definition of done

• Red test preserved and green
• Regression green

Process acknowledgement

• I will preserve the failing regression test, update the issue if the root cause changes, and record any newly discovered bug as its own issue.