fix: add IF NOT EXISTS to migration for idempotency

Added IF NOT EXISTS clauses to CREATE TABLE and CREATE INDEX
statements in 0024_request-filters.sql to ensure migration
idempotency as required by the validation script.

🤖 Generated with [Claude Code](https://claude.com/claude-code)

Co-Authored-By: Claude <[email protected]>

drizzle/0024_request-filters.sql

@@ -1,4 +1,4 @@
-CREATE TABLE "request_filters" (
+CREATE TABLE IF NOT EXISTS "request_filters" (
 	"id" serial PRIMARY KEY NOT NULL,
 	"name" varchar(100) NOT NULL,
 	"description" text,
@@ -13,6 +13,6 @@ CREATE TABLE "request_filters" (
 	"updated_at" timestamp with time zone DEFAULT now()
 );
 --> statement-breakpoint
-CREATE INDEX "idx_request_filters_enabled" ON "request_filters" USING btree ("is_enabled","priority");--> statement-breakpoint
-CREATE INDEX "idx_request_filters_scope" ON "request_filters" USING btree ("scope");--> statement-breakpoint
-CREATE INDEX "idx_request_filters_action" ON "request_filters" USING btree ("action");
+CREATE INDEX IF NOT EXISTS "idx_request_filters_enabled" ON "request_filters" USING btree ("is_enabled","priority");--> statement-breakpoint
+CREATE INDEX IF NOT EXISTS "idx_request_filters_scope" ON "request_filters" USING btree ("scope");--> statement-breakpoint
+CREATE INDEX IF NOT EXISTS "idx_request_filters_action" ON "request_filters" USING btree ("action");