feat(backend): add filter_bins option to github/gitlab backends

[risu729]

Adds filter_bins option to github/gitlab backends to exclude unwanted binaries.

ref: #5788 (comment)
(pypa/hatch is not compatible with GitHub backend, so this doesn't directly solve that problem.)

This is basically the same as Aqua backend's symlink_bins, but binaries listed filter_bins are found from the bin paths, respecting bin_path option too.
https://mise.jdx.dev/dev-tools/backends/github.html#bin-path

Gemini pointed out that we need wrapper scripts to change $0, but I reverted it as it seemed redundant.
Aqua has link option for tools that depend on $0, but it seems such tools are not common.
https://aquaproj.github.io/docs/reference/registry-config/files/#link

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Note

Adds filter_bins to GitHub/GitLab backends to expose only specified binaries via a .mise-bins directory; updates docs and adds an e2e test.

• Backend:
  • Implement filter_bins in src/backend/github.rs:
    • After install, create .mise-bins with symlinks only to specified binaries (create_symlink_bin_dir, get_filter_bins).
    • list_bin_paths returns /.mise-bins when filter_bins is set.
    • Bin discovery now first respects bin_path before fallback search.
• Docs:
  • Add filter_bins option to docs/dev-tools/backends/github.md and docs/dev-tools/backends/gitlab.md with examples and behavior notes.
• Tests:
  • Add e2e/backend/test_github_filter_bins validating .mise-bins contains only pandoc for github:jgm/pandoc.

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[Copilot]

Pull request overview

This pull request adds a filter_bins option to the GitHub and GitLab backends, allowing users to selectively expose only specific binaries from a tool installation on PATH. This is useful for tools that bundle extra binaries or dependencies that users don't want exposed.

Key changes:

• Implements filter_bins option that accepts a comma-separated list of binary names to expose
• Creates a .mise-bins directory with symlinks only to specified binaries
• Refactors discover_bin_paths to be reused by the filtering logic
• Adds comprehensive documentation and e2e test for the new functionality

Reviewed changes

Copilot reviewed 4 out of 4 changed files in this pull request and generated no comments.

File	Description
src/backend/github.rs	Implements filter_bins functionality including get_filter_bins() and create_symlink_bin_dir() methods; refactors bin path discovery logic
e2e/backend/test_github_filter_bins	Adds e2e test using pandoc to verify that filtered binaries are correctly symlinked while others are excluded
docs/dev-tools/backends/github.md	Documents the new filter_bins option with usage examples and behavior description
docs/dev-tools/backends/gitlab.md	Documents the new filter_bins option with usage examples and behavior description

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[jdx]

bugbot run

[cursor]

Bug: Empty filter_bins value hides all binaries unexpectedly

The get_filter_bins function returns Some(vec![]) when filter_bins is set to an empty or whitespace-only value. Since list_bin_paths checks .is_some() to decide whether to use the .mise-bins directory, an empty filter_bins causes the tool to be installed with no binaries exposed on PATH. Users who accidentally set filter_bins="" would see the installation succeed but be unable to run any commands. The function could return None when the resulting vector is empty to treat this as "option not set."