Implement verbose generator parsing

[derselbst]

This PR adds detailed explanations about why fluidsynth drops certain generator. It also promotes some out of memory messages to PANIC level.

Resolves #829.

[Copilot]

Pull Request Overview

This PR implements verbose generator parsing for fluidsynth soundfont loading by adding detailed explanations when generators are dropped or invalid. It also promotes out-of-memory error messages from ERR to PANIC level for better visibility of critical failures.

• Enhances the fluid_gen_name() function to handle invalid generator IDs
• Adds comprehensive logging messages explaining why generators are discarded during soundfont parsing
• Promotes out-of-memory log messages from ERR to PANIC level across the codebase

Reviewed Changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 4 comments.

File	Description
src/synth/fluid_gen.c	Updates fluid_gen_name() to return string representation of invalid generator IDs
src/sfloader/fluid_sffile.c	Adds detailed logging for dropped generators and promotes OOM messages to PANIC level

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[sonarqubecloud]

Quality Gate failed

Failed conditions
9.2% Duplication on New Code (required ≤ 5%)

See analysis details on SonarQube Cloud