8174b7f0c0
Replace parallel features/features_de lists in PLAN_FEATURES with
feature_keys (translation key references). Update waitlist.html and
signup_step_1.html to iterate over plan.feature_keys and render
{{ t[key] }} instead of raw strings.
Replace is_en ternaries in businessplan.py with t = get_translations(language)
and t["bp_*"] lookups for all 9 section headings.
Adds 25 new keys (1197 → 1222): plan_basic_f1-7, plan_growth_f1-4,
plan_pro_f1-5, bp_title, bp_exec_summary, bp_investment, bp_operations,
bp_revenue, bp_annuals, bp_financing, bp_metrics, bp_cashflow_12m.
Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>