feat(app): rank and highlight skill search matches

[oxwen11]

Requirement

Skill search was a case-insensitive substring over name, description, and the full source path. It did not rank hits and did not mark the matched letters. agent browser missed agent-browser, and a path fragment such as pi matched every skill under ~/.pi.

Expected behavior

The Skills page and the / menu rank skills by name match, then description. -, _, /, and spaces are equivalent. The winning field bolds matched letters and dims the rest. Commands stay above skills and keep their existing prefix rank. An empty query keeps the original order.

Changes and risks

Shared matcher in apps/app/src/lib/skill-search.ts, used by the Skills panel and slash-command filter. No stored data or contract change. Query skill no longer returns every skill through a keyword, and the source path is no longer searched.

Verification

• 2975fd39: pnpm --filter @getpie/app exec vitest run src/lib/skill-search.test.ts src/features/chat/components/input/slash-command-suggestions.test.ts — 2 files, 7 passed.
• pnpm exec turbo run typecheck --filter=@getpie/app — passed on the pre-move tree. The move only changed import paths and replaced a fragment with a span.
• Isolated pie-verify web run 20261001T060848Z-26966: Plugins → Skills, search skill creator marks skill and creator and leaves the hyphen unmatched. Draft /skill uses the same marks.
• The unfiltered screenshot and recording were not attached: they list local skills, including a personal bot skill.
• Browser vitest for slash-command-menu.test.tsx was not run.

[oxwen11]

Search result and slash-menu marks. Unfiltered list and recording omitted because they show local skills.

[github-actions]

React Doctor found no new issues. 🎉

_{Reviewed by React Doctor for commit 2975fd3.}

[pkg-pr-new]

npx https://pkg.pr.new/oxwen11/pie/@getpie/cli@430

commit: 2975fd3

[oxwen11]

auto-merge: no

head: 2975fd39c2dbbfefdb177554b9f320113cada411

Fail closed on exclusions + no matching allowed group:

• feature / new functional product behavior: apps/app/src/lib/skill-search.ts and slash-command-suggestions.ts change slash/skill ranking and filtering (new searchSkills path, match on items, reworked filterSlashCommandItems / rankCommandItems).
• new component: adds apps/app/src/lib/highlighted-match.tsx and wires HighlightedMatch into slash-command-menu.tsx and skills-panel.tsx — not presentation-only restore of existing chrome.
• Not docs/tooling, not mechanical lint-format, not ui-presentation (new DOM/match ranges + search control flow).

Din review-first; no merge.