feat(tasks): route local skill tags through the cloud prompt pipeline

[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
• feat(tasks): route local skill tags through the cloud prompt pipeline #2925 👈 (View in Graphite)
• 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 8422a11.}

[greptile-apps]

_{Reviews (1): Last reviewed commit: "feat(tasks): route local skill tags thro..." | Re-trigger Greptile}

[greptile-apps]

Comments Outside Diff (1)

1. packages/core/src/sessions/sessionService.ts, line 2507-2511 (link)

   Double-resolve of skill command prompt on terminal-status path

   sendCloudPrompt resolves the prompt via resolveCloudPrompt before calling resumeCloudRun (line ~2253: return this.resumeCloudRun(session, normalizedPrompt)), and resumeCloudRun then calls resolveCloudPrompt again on the already-resolved prompt. If resolveLocalSkillCommandPrompt performs any side effects — reading local skill files, packaging archives, or making network calls — those operations execute twice. A concrete failure scenario: skill bundle artifacts could be uploaded twice, or file handles left open by the first pass could conflict with the second.

   Either remove resolveCloudPrompt from resumeCloudRun (since sendCloudPrompt is currently its only caller and already hands it a normalized prompt), or pass the raw prompt to resumeCloudRun from sendCloudPrompt and keep resolution inside resumeCloudRun exclusively.

_{Reviews (2): Last reviewed commit: "feat(tasks): route local skill tags thro..." | Re-trigger Greptile}