Fix wavedash dev for Ruffle and JsDos engines

[cloud9c]

Summary

• wavedash dev failed with "Engine config requires an entrypoint" for Ruffle and JsDos projects
• Root cause: the dev command called entrypoint() for all three engine types (Custom, JsDos, Ruffle), but entrypoint() only reads from [custom].entrypoint
• Fix: only require entrypoint() for Custom engines; for Ruffle/JsDos, pass executable_entrypoint_params() instead — matching the existing build push logic

Test plan

• Run wavedash dev from a project with a [ruffle] config — should launch dev server without error
• Run wavedash dev from a project with a [jsdos] config — should work similarly
• Run wavedash dev from a project with a [custom] config — should still require entrypoint as before

🤖 Generated with Claude Code

[claude]

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Code Review

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Fix is correct and well-scoped. The root cause analysis in the PR description is accurate: the original code called entrypoint() (which only reads [custom].entrypoint) for all three engine types, so JsDos/Ruffle would always error with "Engine config requires an entrypoint".

Change 1 — entrypoint variable (src/dev/mod.rs:66-75)

// Before: matched Custom | JsDos | Ruffle → error for JsDos/Ruffle since entrypoint() returns None
// After: only matches Custom
let entrypoint = if matches!(engine_kind, EngineKind::Custom) {

Correct. entrypoint (a plain &str) is only meaningful for Custom engines, where it maps to [custom].entrypoint. JsDos/Ruffle use the structured entrypoint_params path instead.

Change 2 — entrypoint_params match arm (src/dev/mod.rs:91-92)

// Before: JsDos | Ruffle => None
// After:  JsDos | Ruffle => wavedash_config.executable_entrypoint_params()

Correct. This now matches the existing build push logic in src/builds.rs:200. The build_sandbox_url function in src/dev/sandbox.rs already handles both entrypoint and entrypoint_params independently as Option values, so this wires up correctly.

Minor observations

1. EngineKind::Custom => None in the entrypoint_params match — intentional and correct: Custom engines pass their entrypoint via the entrypoint string param, not entrypoint_params. No issue.

2. executable_entrypoint_params() can return None (if neither jsdos nor ruffle config section is present) — this would be a config loading error caught earlier by engine_type(), so it's not a new risk introduced here.

No issues found. The change is minimal, accurate, and consistent with the build push path.