chore: strip remaining pre-fork version references

Second pass — removes chat-switchboard version numbers from config
field docs, section headers, file headers, and test comments. These
were pre-fork version tags that don't apply to switchboard-core.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

server/store/sqlite/workflows.go

@@ -418,7 +418,7 @@ func nullIfEmpty(s string) interface{} {
 	return s
 }
 
-// ── Instances (v0.3.1) ──────────────────────
+// ── Instances ──────────────────────
 
 func (s *WorkflowStore) CreateInstance(ctx context.Context, inst *models.WorkflowInstance) error {
 	inst.ID = store.NewID()
@@ -597,7 +597,7 @@ func (s *WorkflowStore) ListActiveInstances(ctx context.Context) ([]models.Workf
 	return result, rows.Err()
 }
 
-// ── Assignments (v0.3.1) ────────────────────
+// ── Assignments ────────────────────
 
 func (s *WorkflowStore) CreateAssignment(ctx context.Context, a *models.WorkflowAssignment) error {
 	a.ID = store.NewID()
@@ -690,7 +690,7 @@ func (s *WorkflowStore) ListAssignmentsByUser(ctx context.Context, userID string
 	return s.queryAssignments(ctx, q, args...)
 }
 
-// ── Signoffs (v0.3.4) ─────────────────────────
+// ── Signoffs ─────────────────────────
 
 func (s *WorkflowStore) CreateSignoff(ctx context.Context, so *models.WorkflowSignoff) error {
 	so.ID = store.NewID()