feat(psql): add PostgreSQL install script and path configuration

psql/.psql-version

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+18

psql/install.sh

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+#!/usr/bin/env bash
+#
+# Install PostgreSQL.
+
+set -euo pipefail
+
+DOTFILES_ROOT=$(cd "$(dirname "${BASH_SOURCE[0]}")"/..; pwd)
+source "$DOTFILES_ROOT/lib/logger.sh"
+
+info 'Installing PostgreSQL'
+if ! command -v brew > /dev/null; then
+  user 'Homebrew not found. Would you like to install Homebrew first? (y/n)'
+  read -r -p '> ' install_brew
+  if [[ "$install_brew" =~ ^[Yy]$ ]]; then
+    source "$DOTFILES_ROOT/homebrew/install.sh"
+    source "$DOTFILES_ROOT/homebrew/path.zsh"
+  else
+    fail 'Homebrew is required to install PostgreSQL.'
+    exit 1
+  fi
+fi
+# Get available PostgreSQL versions
+available_versions=$(brew search postgresql@ | grep -E '^postgresql@[0-9.]+$' | sed 's/postgresql@//')
+user 'Which PostgreSQL version would you like to install?'
+info 'Available versions:'
+info_list "$available_versions"
+read -r -p '> ' psql_version
+info "Installing PostgreSQL@$psql_version"
+brew install postgresql@"$psql_version"
+# Store the selected version for path.zsh
+echo "$psql_version" > "$(dirname "${BASH_SOURCE[0]}")/.psql-version"
+success "PostgreSQL@$psql_version installed"

psql/path.zsh

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+if [[ -f "$(dirname "$0")/.psql-version" ]]; then
+  psql_version=$(cat "$(dirname "$0")/.psql-version")
+  export PATH="/opt/homebrew/opt/postgresql@$psql_version/bin:$PATH"
+  export LDFLAGS="-L/opt/homebrew/opt/postgresql@$psql_version/lib"
+  export CPPFLAGS="-I/opt/homebrew/opt/postgresql@$psql_version/include"
+  export PKG_CONFIG_PATH="/opt/homebrew/opt/postgresql@$psql_version/lib/pkgconfig"
+fi