fix(cli): Resolve {env:VAR} and {file:path} patterns in OPENCODE_CONFIG_CONTENT

[beppe2880]

Problem

OCX passes {env:VAR} patterns as literal strings in OPENCODE_CONFIG_CONTENT.
OpenCode only resolves these patterns when reading files from disk (load()),
not when receiving config via OPENCODE_CONFIG_CONTENT (JSON.parse only).

This breaks any MCP server using {env:VAR} in its environment or headers fields
when launched through ocx oc.

Fix

Resolve {env:VAR} patterns on the serialized JSON string in buildOpenCodeEnv,
matching OpenCode's own resolution approach (string replace before parse).

---

Summary by cubic

Resolve {env:VAR} and {file:path} placeholders in OPENCODE_CONFIG_CONTENT before parsing so MCP servers using env vars or file-based secrets work when launched via ocx oc.

• Bug Fixes
  • Added resolve-config utility (resolveEnvVars, resolveFilePatterns, resolveConfigPatterns); exported via utils.
  • Resolve patterns in runOpencode and pass the pre-resolved serialized JSON as configContent to buildOpenCodeEnv (replaces mergedConfig param).
  • Updated tests for env/file patterns, JSON-safe escaping, path resolution, ~ expansion, and the buildOpenCodeEnv configContent signature.

^{Written for commit e4238f2. Summary will update on new commits.}

[cubic-dev-ai]

No issues found across 4 files

---

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[cubic-dev-ai]

No issues found across 4 files

[kdcokenny]

Ah very interesting! Do you know if this is the same for their other patterns like file:?

[codecov]

Codecov Report

❌ Patch coverage is 76.74419% with 10 lines in your changes missing coverage. Please review.
✅ Project coverage is 48.34%. Comparing base (9e72ac9) to head (e4238f2).
⚠️ Report is 2 commits behind head on main.

Files with missing lines	Patch %	Lines
packages/cli/src/commands/opencode.ts	25.00%	6 Missing ⚠️
packages/cli/src/utils/resolve-config.ts	88.23%	4 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #128      +/-   ##
==========================================
+ Coverage   48.05%   48.34%   +0.28%     
==========================================
  Files          46       47       +1     
  Lines        4903     4944      +41     
==========================================
+ Hits         2356     2390      +34     
- Misses       2547     2554       +7     

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[beppe2880]

Yes, {file:path} has the same bug, both patterns are resolved in load() which OPENCODE_CONFIG_CONTENT bypasses entirely. I was already planning a follow-up PR for it. Would you prefer that as a separate PR or should I add it to this one?

[kdcokenny]

Yes, {file:path} has the same bug, both patterns are resolved in load() which OPENCODE_CONFIG_CONTENT bypasses entirely. I was already planning a follow-up PR for it. Would you prefer that as a separate PR or should I add it to this one?

It would be great if you did those in this PR! I would greatly appreciate it.

[beppe2880]

Hey! Just pushed {file:path} support to this PR. Same approach as {env:VAR} — patterns are resolved on the serialized JSON string before passing it to OPENCODE_CONFIG_CONTENT. Let me know if it looks good or if there's anything else I can do!

[beppe2880]

@kdcokenny ready for review when you get a chance!

[kdcokenny]

Thank you!

[kdcokenny]

Looks like the core issue has been fixed anomalyco/opencode#13384