feat(tasks): surface local skills in the composer and upload on send

[tatoalo]

Problem

for cloud tasks, local skill invocations only sent the slash command text. User-local and repo-local skills were available in the local editor but not in the cloud sandbox

Changes

• let's bundle uploadable local skills into zip artifacts with SHA-256 metadata and send them through the existing cloud artifact upload flow.

• install skill_bundle artifacts in the agent server before prompt delivery, inject the bundled skill instructions for the invoked turn, and suppress the raw slash command from the model-facing prompt so local skills behave like actual skills rather than unsupported commands

• refresh slash command metadata when a follow-up command is submitted, so newly created local skills can be selected and invoked without starting a brand-new task.

closes #2260

[tatoalo]

Warning

This pull request is not mergeable via GitHub because a downstack PR is open. Once all requirements are satisfied, merge this PR as a stack on Graphite.
Learn more

• feat(tasks): surface local skills in the composer and upload on send #2926 👈 (View in Graphite)
• feat(tasks): route local skill tags through the cloud prompt pipeline #2925
• feat(tasks): install and apply skill bundle artifacts in the sandbox #2924
• feat(tasks): bundle local skills into sha256-verified zip artifacts #2923
• feat(tasks): add skill bundle artifact contracts and metadata types #2922
• main

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[github-actions]

React Doctor found no issues in the changed files. 🎉

_{Reviewed by React Doctor for commit 17746ff.}

[greptile-apps]

Comments Outside Diff (1)

1. packages/ui/src/features/task-detail/components/TaskInput.tsx, line 1040-1061 (link)

   Duplicated skill-to-command mapping

   The inline spread source !== "bundled" ? { localSkill: { name, source, path } } : {} appears in at least four places: TaskInput.tsx, PromptInput.tsx, useSessionCallbacks.ts (the fallback fetch), and sessionServiceHost.ts (resolveLocalSkillCommandPrompt). Extracting a shared helper such as skillToEditorCommand(skill): EditorAvailableCommand would keep this conversion in one place; if the localSkill shape or the "bundled" check ever changes, only one site needs updating.

   Context Used: Do not attempt to comment on incorrect alphabetica... (source)

   Note: If this suggestion doesn't match your team's coding style, reply to this and let me know. I'll remember it for next time!

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[greptile-apps]

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