fix(db): add FK constraints, indexes, transaction fixes, and hook_executions tenant isolation (migrations 082-083) (#1246)

Co-authored-by: Bruno Clermont <bruno.clermont@gmail.com>

internal/hooks/dispatcher.go

@@ -438,6 +438,7 @@ func (d *stdDispatcher) writeExec(ctx context.Context, cfg HookConfig, ev Event,
 	exec := HookExecution{
 		ID:         uuid.New(),
 		HookID:     &hookID,
+		TenantID:   &ev.TenantID,
 		SessionID:  ev.SessionID,
 		Event:      ev.HookEvent,
 		InputHash:  inputHash,

internal/hooks/types.go

@@ -186,7 +186,8 @@ type HookConfig struct {
 // error_detail (BYTEA) is AES-256-GCM encrypted before storage.
 type HookExecution struct {
 	ID          uuid.UUID  `json:"id"`
-	HookID      *uuid.UUID `json:"hook_id,omitempty"` // NULL when hook deleted (ON DELETE SET NULL)
+	HookID      *uuid.UUID `json:"hook_id,omitempty"`  // NULL when hook deleted (ON DELETE SET NULL)
+	TenantID    *uuid.UUID `json:"tenant_id,omitempty"`
 	SessionID   string     `json:"session_id"`
 	Event       HookEvent  `json:"event"`
 	InputHash   string     `json:"input_hash"`  // canonical-JSON sha256, 64 hex chars