Skill picker: display argument-hint inline and make (plugin-name) annotation suppressible

Summary

In Claude Code 2.1.119, plugin-provided skills render differently from slash commands in the / autocomplete picker in two ways that seem inconsistent / undocumented:

1. argument-hint: is not shown inline for skills. A slash command displays /color <red|blue|green|yellow|...> — the arg-hint is inline on the same line. A plugin skill with identical argument-hint: frontmatter only shows its description:. The hint value is ignored by the picker.

1. The (plugin-name) annotation on plugin skills is not suppressible. Plugin skills render as /skill-name (plugin-name) description…. There is no frontmatter option to hide the annotation. The skills docs reference argument-hint as "Hint shown during autocomplete" but don't describe this difference from commands, and the (plugin-name) annotation isn't documented in the skills frontmatter reference.

Reproduction

Create a plugin skill:

plugins/myplugin/skills/foo/SKILL.md
---
name: foo
description: Do the foo thing.
argument-hint: "[target] [--flag]"
---

Type / in the picker and observe /foo (myplugin) Do the foo thing. — the argument-hint is absent. Compare to a local slash command with the same frontmatter in .claude/commands/foo.md which does render the hint inline.

Why it matters

The skills docs say "Custom commands have been merged into skills" and that a commands/foo.md and skills/foo/SKILL.md "both create /foo and work the same way." Plugin authors are migrating commands/ → skills/ based on this guidance, but the picker UX regresses: users lose the inline argument hint they relied on.

Requests

1. Render argument-hint: inline in the picker for skills, matching slash-command behavior. This is what the docs imply (\"hint shown during autocomplete\") and what plugin authors expect after the commands→skills merge.
2. Document the (plugin-name) annotation in the skills frontmatter reference, and consider an opt-out (frontmatter flag like show-plugin-name: false, or a per-plugin setting). The annotation is useful for distinguishing sources but shouldn't be the only thing that differentiates a skill from a command visually.

Environment

• Claude Code: 2.1.119 (native install, macOS Darwin 25.3.0)
• Plugin: published via marketplace (git source), 18 skills + 1 command migrated to skills-only
• Behavior confirmed in the / picker on fresh sessions