config.rs: typed HostConfig parsed ONCE from env (idd_push/encoder_pref/no_helper/force_helper), replacing per-call env::var re-reads (PUNKTFUNK_ENCODER was re-read on EVERY windows_resolved_backend() call; PUNKTFUNK_IDD_PUSH is read 8x across the host — the recompute that lets capture + encode disagree on the backend, plan §2.4). Migrated the two highest-churn dispatch reads onto it (encode::windows_resolved_backend, punktfunk1::should_use_helper). Behavior-identical: the env is constant for the process lifetime (the service loads host.env before launch), so a lazily-parsed global == parsed-once-at-startup.
docs/windows-host-goal1-plan.md: the ORDERED, independently-shippable execution plan for Goal-1 (the plan's biggest unstarted goal — a from-scratch layered host architecture). Six behavior-preserving, box-verified stages (HostConfig -> SessionPlan -> SessionContext/SessionFactory -> seam-trait tightenings -> src/windows tree), because the host is live-validated and a monolithic rewrite would strand it broken. Stage 1 done here; stages 3-5 rewire the deployed path and require on-glass re-test.
Verified: Linux + box (--features nvenc) cargo check clean.
Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
enricobuehler
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