docs(contributing): make bundled integration skills the path for plugin maintainers

[Leo310]

What

Rewrites the skill guidance in CONTRIBUTING to separate two things the old text conflated: sharing a skill and contributing one.

A skill someone copies into their vault never updates. A bundled skill is seeded automatically and reconciled on later releases (reconcileBundledSkill), so improvements reach vaults that already have it. And where no bundled skill exists for a plugin, seedIntegrationSkill falls back to a generated template that asks the agent to introspect the plugin's API at runtime.

That makes bundling the thing worth contributing, and the plugin's own maintainer the person best placed to do it — they're the ones who'd want to replace the introspection fallback with a real guide.

Changes

• "Ways to contribute" splits into Share skills and agents (Show and tell, for the low-friction case) and Contribute a bundled skill, which names plugin maintainers explicitly.
• New Integration skills, for plugin maintainers subsection: where the file goes, the metadata.linkedPlugin key, CURATED_PLUGIN_INTEGRATIONS for a display name, and the point that auto-discovery already finds any plugin exposing an api — the skill is what makes the agent good at using it.
• Notes the shippedSkills.ts version-history requirement for later edits, since that's non-obvious and enforced by test/skills/shippedSkillHistory.test.ts.
• The general skill recipe now explains on-demand loading (why description carries the weight) and asks authors to test that a skill stays quiet when it shouldn't fire.

Note on the earlier version of this PR

This PR originally pointed skill contributions at a separate s2b-dev/skills repository. That was the wrong call and has been dropped: a standalone repo can only offer manual copies, which is strictly worse than bundling for exactly the contributors it was meant to serve. The repo is being deleted; nothing external ever landed in it.

How I tested it

Docs only, no code changed. Every path and claim checked against the source: seedIntegrationSkill / reconcileBundledSkill in SkillsService.ts, CURATED_PLUGIN_INTEGRATIONS and pluginExposesApi in pluginIntegrations.ts, and test/skills/shippedSkillHistory.test.ts for the enforcement claim.

AI assistance

Drafted with Claude Code; the maintainer reviewed every file.

[greptile-apps]

Greptile Summary

The contribution guide now distinguishes community-shared skills and agents from bundled integration skills.

• Directs general sharing to Show and Tell.
• Expands guidance for authoring, testing, and maintaining bundled integration skills.

Confidence Score: 5/5

The PR appears safe to merge.

No blocking failure remains.

Important Files Changed

Filename	Overview
CONTRIBUTING.md	Clarifies the separate contribution paths for shared skills and agents versus bundled plugin integrations.

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