chore: add termux pypi repo before installimg requirements and simplify logic in scripts

scripts/install_termux_reqs.sh

@@ -1,10 +1,11 @@
 #!/usr/bin/env bash
 
-if ! echo "${PATH}" | grep -qi "com.termux"; then
-  echo "Not a termux Env, Skipping..."
-  exit
-fi
+grep -qi "com.termux" <<< "$PATH" || { echo "Not a termux Env, Skipping..."; exit; }
+
+mkdir -p "${HOME}/.config/pip" /dev/null 2>&1
+
+echo -e '[global]\nextra-index-url = https://termux-user-repository.github.io/pypi/' > "${HOME}/.config/pip.conf"
 
 ./scripts/install_ub_core.sh
 
-grep -Ev "^#|google-generativeai|pillow" req.txt | xargs -n 1 pip install
+grep -Ev "^#|openai" req.txt | xargs -n 1 pip install