S12 - turned schedule status into enum and some other review comments

specs/S12-validation.md

@@ -22,8 +22,8 @@ without event replay. Run identifiers deduplicate completion notifications.
 ## Validation
 
 - Maven verify: 60 backend tests passed, plus 19 standards-checker regression tests.
-- Backend line coverage: 1349/1387, or 97.26%, above the required 80%.
-- Frontend: 29 unit tests, production build and ESLint.
+- Backend line coverage: 1346/1384, or 97.25%, above the required 80%.
+- Frontend: 30 unit tests, production build and ESLint.
 - Playwright: three real REST/browser scenarios, including scheduling completion,
   result summaries, a completion snackbar, reloading to recover the latest result
   and suppression of old notifications after reload.
@@ -32,12 +32,17 @@ without event replay. Run identifiers deduplicate completion notifications.
 - Background tests cover duplicate exclusion, parallel shows, stale-result
   rejection, preserved assignments, failure outcomes and retry after failure.
 - Frontend tests cover missed completion after disconnect, reconnection, heartbeat
-  handling, deduplication and completion arriving before the POST response.
+  handling, deduplication, completion arriving before the POST response and a
+  locally started run completing before the first successful SSE connection.
 - Real solver tests cover phase/discovery callbacks, distinct infeasible/no-solution
   outcomes and objective-summary definitions including coach exemptions.
 
 ## Manual standards assessment
 
+Scheduling states and phases use backend enums and frontend string unions while
+preserving their JSON names. Initial SSE recovery notifies for locally tracked
+running tasks while suppressing historical completions.
+
 No waivers or weakened checks were introduced. The architecture tests pass.
 New records contain immutable values; the SSE snapshot defensively copies its
 list. The ten-component SchedulingRun record groups run identity, timestamps,
@@ -47,14 +52,14 @@ framework-independent domain types; OR-Tools remains encapsulated in solver.
 
 Retained review signals:
 
-- SchedulingRuns fan-out (25): task orchestration uses JDK executor/collection
+- SchedulingRuns fan-out (26): task orchestration uses JDK executor/collection
   types, the scheduling port and immutable input/progress/result/status models.
   Its injected dependencies remain two; splitting these short lifecycle methods
   would distribute the shared publication and run-slot ordering.
 - SchedulingEventsResource fan-out (16): SSE/Mutiny transport, JSON envelope and
   service subscription types are confined to the REST adapter.
 - OrToolsSchedulingEngine fan-out (21), solve cognitive complexity (11) and
-  length (40 code lines): the ordered three-stage loop retains deadline and
+  length (41 code lines): the ordered three-stage loop retains deadline and
   earlier-feasible-result fallback behavior while publishing phase/discovery.
   requireSolution cyclomatic complexity (8) retains explicit mappings for stable
   failure outcomes and their human-readable explanations.