[CI] Restore green main after Clippy and generated-doc drift #407

Outcome

Restore a truthful green main baseline before adding more Renderflow product surface.

Observed baseline

Checked on 2026-09-13 against main at 58aa2cad8ba9e2374d0e7a1bf5277052ae40838c.

Two current required checks are failing:

1. Build and test / Clippy
   • crates/renderflow-core/src/commands/build.rs
   • run_selection currently has eight parameters and fails under -D warnings with clippy::too_many_arguments.
2. Generated documentation drift
   • docs/user-guide/tool-registry.md does not match the canonical generator output.
   • The reported delta includes HandBrake and Lulu rules/capabilities.

The web checks, installer, Snap, and AUR jobs observed in the same baseline are succeeding. This is a focused baseline-repair issue, not a reopening of the older packaging incident resolved by #351.

Scope

• Refactor the wide run_selection call boundary into a typed request/options object, or document a narrower alternative that preserves behavior.
• Do not silence the lint globally or weaken -D warnings.
• Regenerate docs/user-guide/tool-registry.md through the canonical generator and commit the exact generated result.
• Confirm the underlying registry sources for HandBrake and Lulu are intentional and covered by the documentation contract.
• Add or strengthen a regression check if the current checks can drift without a locally reproducible failure.
• Run the complete required validation suite and record the evidence.

Acceptance criteria

• cargo fmt --check passes.
• Clippy passes with warnings denied for the same targets/features used in CI.
• The relevant unit/integration tests pass.
• The generated-document check is clean from a fresh checkout.
• No lint, documentation, or workflow gate is bypassed to obtain green status.
• Required GitHub Actions checks are green on the resulting main commit.
• Completion evidence is linked from this issue and reconciled with the universal artifact roadmap in Roadmap: universal artifact forest, maximal Renderflow profile, and Flow orchestration readiness #367.

Related work

• Roadmap: universal artifact forest, maximal Renderflow profile, and Flow orchestration readiness #367 — universal artifact forest and Flow-suite readiness
• [Publication] Add localization-ready layered page composition and locale render targets #406 — localization-ready layered page composition