Do not replace legacy FX with new PS FX

[DedeHai]

as discussed, we should keep legacy functions and FX if possible. Since PS replacements is purely a flash saving matter we should not enforce progress to users until the need for reducing flash size arises.

What this PR does is enable the WLED_PS_DONT_REPLACE_FX flag on all builds, keeping all legacy FX.

edit: flash cost is 8k

Summary by CodeRabbit

• Chores
  • Added a new build configuration flag to provide an option for controlling effects behavior during firmware compilation.

_{✏️ Tip: You can customize this high-level summary in your review settings.}

[coderabbitai]

Walkthrough

A build flag WLED_PS_DONT_REPLACE_FX is added to platformio.ini with a comment indicating that particle system replacement effects should not replace classic effects until flash memory is exhausted.

Changes

Cohort / File(s)	Summary
Build configuration platformio.ini	Added build flag -D WLED_PS_DONT_REPLACE_FX to control particle system replacement behavior, with documentation note that PS replacement FX should not replace classic FX until flash is exhausted

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~2 minutes

• Single configuration line addition with inline documentation
• No logic changes or code modifications

Possibly related PRs

• refined PS replacement ifdefs #5103 — Refactors and refines PS-replacement ifdefs that reference/utilize the new WLED_PS_DONT_REPLACE_FX macro with per-effect guards
• Adding Particle System with many new FX #4506 — Also modifies particle system build-time flags; introduces WLED_DISABLE_PARTICLESYSTEM1D/2D controls alongside particle system code

Suggested reviewers

• softhack007
• netmindz

Pre-merge checks and finishing touches

✅ Passed checks (3 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title accurately reflects the main change: adding the WLED_PS_DONT_REPLACE_FX flag to prevent legacy FX replacement with new PS FX in platformio.ini.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.

✨ Finishing touches

• 📝 Generate docstrings

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment

---

Thanks for using CodeRabbit! It's free for OSS, and your support helps us grow. If you like it, consider giving us a shout-out.

❤️ Share

• X
• Mastodon
• Reddit
• LinkedIn

_{Comment @coderabbitai help to get the list of available commands and usage tips.}