feat: add support for mise.toml file

[gperdomor]

Description:
This MR add support for mise.toml file - https://mise.jdx.dev

Related issue:
#1304

Check list:

• Mark if documentation changes are required.
• Mark if tests were added or updated to cover the changes.

[Copilot]

Pull Request Overview

This PR adds support for parsing Node.js versions from mise.toml configuration files, extending the action's capability to read version specifications from mise tool manager configurations.

Key Changes:

• Added TOML parsing functionality to extract Node.js versions from mise.toml files
• Updated documentation to include mise.toml as a supported version file format
• Added test coverage for the new TOML parsing feature

Reviewed Changes

Copilot reviewed 4 out of 7 changed files in this pull request and generated 2 comments.

File	Description
src/util.ts	Added TOML parsing logic to extract Node.js version from mise.toml files with support for both string and object formats
package.json	Added js-toml dependency for TOML file parsing
tests/main.test.ts	Added test case for mise.toml format and reorganized imports
README.md	Updated documentation to list mise.toml as a supported version file format

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[gperdomor]

@aparnajyothi-y can you take a look at this please? Sorry for pinging you btw 🙏🏻