feat: update file modes and remove placeholder .env template

Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>

.env

@@ -1,55 +0,0 @@
-# See README.rst for explanations of these.
-# If you add a new learning MFE-specific variable, please note it there!
-
-NODE_ENV='production'
-
-ACCESS_TOKEN_COOKIE_NAME=''
-APP_ID='learning'
-BASE_URL=''
-CONTACT_URL=''
-CREDENTIALS_BASE_URL=''
-CREDIT_HELP_LINK_URL=''
-CSRF_TOKEN_API_PATH=''
-DISCOVERY_API_BASE_URL=''
-DISCUSSIONS_MFE_BASE_URL=''
-DISCOUNT_CODE_INFO_URL=''
-ECOMMERCE_BASE_URL=''
-ENABLE_JUMPNAV='true'
-ENABLE_NOTICES=''
-ENTERPRISE_LEARNER_PORTAL_HOSTNAME=''
-ENTERPRISE_LEARNER_PORTAL_URL=''
-EXAMS_BASE_URL=''
-FAVICON_URL=''
-IGNORED_ERROR_REGEX=''
-INSIGHTS_BASE_URL=''
-LANGUAGE_PREFERENCE_COOKIE_NAME=''
-LMS_BASE_URL=''
-LOGIN_URL=''
-LOGOUT_URL=''
-LOGO_URL=''
-LOGO_TRADEMARK_URL=''
-LOGO_WHITE_URL=''
-LEGACY_THEME_NAME=''
-MARKETING_SITE_BASE_URL=''
-ORDER_HISTORY_URL=''
-PROCTORED_EXAM_FAQ_URL=''
-PROCTORED_EXAM_RULES_URL=''
-REFRESH_ACCESS_TOKEN_ENDPOINT=''
-SEARCH_CATALOG_URL=''
-SEGMENT_KEY=''
-SESSION_COOKIE_DOMAIN=''
-SITE_NAME=''
-SOCIAL_UTM_MILESTONE_CAMPAIGN=''
-STUDIO_BASE_URL=''
-SUPPORT_URL=''
-SUPPORT_URL_CALCULATOR_MATH=''
-SUPPORT_URL_ID_VERIFICATION=''
-SUPPORT_URL_VERIFIED_CERTIFICATE=''
-TERMS_OF_SERVICE_URL=''
-TWITTER_HASHTAG=''
-TWITTER_URL=''
-USER_INFO_COOKIE_NAME=''
-OPTIMIZELY_FULL_STACK_SDK_KEY=''
-SHOW_UNGRADED_ASSIGNMENT_PROGRESS=''
-# Fallback in local style files
-PARAGON_THEME_URLS={}