feat: save and load ir_gain and last selected preset

[OpenSauce]

No description provided.

[Copilot]

Pull request overview

This PR adds persistence for IR gain values in presets and remembers the last selected preset across application restarts. The changes enable users to save their IR cabinet gain settings as part of presets and automatically load their most recently used preset when the application starts.

• Added ir_gain field to the Preset structure with serde default support for backward compatibility
• Added selected_preset field to Settings to persist the last opened preset
• Updated preset loading/saving flow to handle IR gain values throughout the application

Reviewed changes

Copilot reviewed 7 out of 7 changed files in this pull request and generated 2 comments.

Show a summary per file

File	Description
src/settings/mod.rs	Added selected_preset field to persist the last selected preset name
src/preset/mod.rs	Added ir_gain field with default value of 0.1 and updated constructor signature
src/gui/handlers/preset.rs	Updated preset handler to propagate ir_gain through save/load operations and made load_preset_by_name public
src/gui/components/ir_cabinet_control.rs	Updated constructor to accept gain parameter instead of hardcoding the default value
src/gui/app.rs	Added logic to load last selected preset on startup, save selected preset to settings, and pass ir_gain to preset operations
presets/Sabbath.json	Added ir_name and ir_gain fields to the preset
presets/Petrucci.json	Added ir_gain field to the preset

Comments suppressed due to low confidence (1)

src/gui/app.rs:67

• The IR gain from the loaded preset is set on the UI component but is never applied to the audio engine during initialization. After setting up the IR cabinet control with the preset's ir_gain on line 54, you should also call audio_manager.engine().set_ir_gain(preset.ir_gain) to ensure the audio engine uses the correct gain value when the app starts.

        let mut ir_cabinet_control = IrCabinetControl::new(settings.ir_bypassed, preset.ir_gain);
        ir_cabinet_control.set_available_irs(audio_manager.get_available_irs());

        if settings.ir_bypassed {
            audio_manager.engine().set_ir_bypass(true);
        }

        if let Some(ir_name) = preset.ir_name {
            ir_cabinet_control.set_selected_ir(Some(ir_name.clone()));
            audio_manager.engine().set_ir_cabinet(Some(ir_name));
        } else if let Some(first_ir) = ir_cabinet_control.get_selected_ir() {
            ir_cabinet_control.set_selected_ir(Some(first_ir.clone()));
            audio_manager.engine().set_ir_cabinet(Some(first_ir));
        }

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[Copilot]

Pull request overview

Copilot reviewed 7 out of 7 changed files in this pull request and generated 3 comments.

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