Use toml for config file

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The issue title suggests changing the configuration file format to TOML. First, locate the current config file handling in the codebase, likely in a config/ or internal/ directory. Identify the existing format (e.g., JSON, YAML) and understand how it's parsed and used. Research Go TOML libraries (e.g., BurntSushi/toml) and plan the migration, ensuring backward compatibility if needed. Check for any tests related to config loading to update.

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