fix(scripts): improve tmux-send.sh reliability and add --paste flag #5450

Job	Run time
build-and-check	2m 29s
test-cli	1m 14s
test-packages/internal	48s
test-.agents	43s
test-common	41s
test-integration-.agents	45s
test-integration-sdk	46s
test-packages/billing	40s
test-integration-common	45s
test-sdk	53s
test-integration-web	41s
test-web	45s
test-integration-packages/billing	46s
test-integration-packages/agent-runtime	41s
test-packages/agent-runtime	59s
test-integration-cli	46s
test-integration-packages/internal	47s
	15m 9s

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