docs(prepare): add all source files to sources

[risu729]

No description provided.

[Copilot]

Pull request overview

This PR updates the documentation table for built-in package manager providers to show all source files (not just lockfiles) that each provider monitors. The table headers are updated from "Lockfile" to "Sources" and "Output" to "Outputs" to better reflect the complete set of files that trigger prepare operations.

Key Changes:

• Updated table column headers to "Sources" (from "Lockfile") and "Outputs" (from "Output")
• Added package manifest files (package.json, pyproject.toml, Gemfile, composer.json) alongside their respective lockfiles in the Sources column
• Maintained accurate output directories and commands for each provider

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[Copilot]

This sentence should be updated to reflect the new "Sources" terminology used in the table above. Since the table now includes all source files (not just lockfiles), this should say "source files" instead of "lockfile". For example: "Built-in providers are only active when explicitly configured in mise.toml and their source files exist."

Suggested change

	Built-in providers are only active when explicitly configured in `mise.toml` and their lockfile exists.
	Built-in providers are only active when explicitly configured in `mise.toml` and their source files exist.