fix(execenv): write OpenCode skills to .opencode/skills/ for native discovery

[AkosSeres]

Background

I found that the OpenCode skill-injection path was not correct for workdir-scoped skills. Earlier code placed skills for the opencode provider under workDir/.config/opencode/skills/, but OpenCode’s workdir/project-scoped skills are discovered from .opencode/skills/ (source: https://opencode.ai/docs/skills/). As a result, injected workspace skills would not land in the path OpenCode scans for project-level skill discovery.

OpenCode still uses the user-level/global path under ~/.config/opencode/skills/<name>/SKILL.md, so the existing local-runtime import/discovery behavior for global skills remains unchanged.

Change

• resolveSkillsDir: route opencode workspace skill injection to workDir/.opencode/skills/ so SKILL.md files and supporting assets land where OpenCode discovers workdir-scoped skills.
• Update doc comments in context.go and runtime_config.go to reference .opencode/skills/ for OpenCode injection.
• Update provider documentation and product overview references from .config/opencode/skills/ to .opencode/skills/ where they describe injected/project-level OpenCode skills.
• Update TestWriteContextFilesOpencodeNativeSkills to lock in .opencode/skills/ behavior and ensure .agent_context/skills/ is no longer created for OpenCode.

Test

go test ./internal/daemon/execenv -run TestWriteContextFilesOpencodeNativeSkills -count=1
ok  github.com/multica-ai/multica/server/internal/daemon/execenv

go test ./internal/daemon/execenv ./internal/daemon -count=1
ok  github.com/multica-ai/multica/server/internal/daemon/execenv
ok  github.com/multica-ai/multica/server/internal/daemon

AI Disclosure

AI tool used: Multica Agent + Hermes Agent

[vercel]

@AkosSeres is attempting to deploy a commit to the IndexLabs Team on Vercel.

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[Bohan-J]

Thanks for the fix — the routing change to .opencode/skills/ is correct, and I verified the OpenCode docs (https://opencode.ai/docs/skills/) confirm .opencode/skills/<name>/SKILL.md is the project-scoped path while ~/.config/opencode/skills/ remains the user-level one. The doc updates and the tightened TestWriteContextFilesOpencodeNativeSkills look great. Locally I ran go test ./internal/daemon/execenv ./internal/daemon ./internal/daemon/repocache -count=1 and everything passes.

One blocking issue before merge:

server/internal/daemon/repocache/cache.go:426 and :458 still exclude the old path. Both call sites do:

for _, pattern := range []string{".agent_context", "CLAUDE.md", "AGENTS.md", ".claude", ".config/opencode"} {
    _ = excludeFromGit(worktreePath, pattern)
}

excludeFromGit writes these patterns into the worktree's .git/info/exclude so injected agent files don't show up in git status or get accidentally staged. Before this PR, OpenCode skills landed in .config/opencode/skills/, which that pattern covered. After this PR they land in .opencode/skills/, but the exclude list still references the stale .config/opencode. The new injection directory is therefore no longer hidden, so any OpenCode task whose agent runs git add -A / git commit -a could pull the injected SKILL.md files into a commit. That's a regression introduced by this PR.

Suggested fix:

for _, pattern := range []string{".agent_context", "CLAUDE.md", "AGENTS.md", ".claude", ".opencode"} {
    _ = excludeFromGit(worktreePath, pattern)
}

It would also be worth adding a small repocache test asserting the new worktree's .git/info/exclude contains .opencode, so future path moves don't silently drop the exclude again.

Unrelated to this PR but worth noting for a follow-up: the same exclude list doesn't cover .cursor/, .kimi/, .kiro/, .pi/, or .github/skills/, even though those providers also inject natively. Probably worth extracting these patterns into a shared constant alongside resolveSkillsDir so they can't drift apart again.

Happy to re-review once the exclude pattern is updated. Thanks!

[AkosSeres]

Thanks @Bohan-J for the review, I fixed your finding!

What changed:

• Replaced the stale repocache git exclude for .config/opencode with .opencode and extract the list into a shared agentGitExcludePatterns for both call sites
• Adds TestCreateWorktreeExcludesOpenCodeSkills; I first confirmed it failed against the stale exclude, then made it pass.

Verified with:

• go test ./internal/daemon/repocache -run TestCreateWorktreeExcludesOpenCodeSkills -count=1
• go test ./internal/daemon/execenv ./internal/daemon ./internal/daemon/repocache -count=1

I pushed this as a separate commit, let me know if I should squash the commits instead.