[codex] Dedupe plugin MCPs by app declaration name

[felixxia-oai]

Context

This is the next step in the plugin auth-routing stack. The earlier PRs make PluginsManager auth-aware and move the broad App/MCP surface decision into that layer. This PR narrows the ChatGPT/SIWC behavior so we only hide a plugin MCP server when it conflicts with an App declaration of the same name.

In product terms: if a plugin exposes both an App route and MCP route for foo, ChatGPT/SIWC sessions should use the App route for foo. If the same plugin also exposes a separate MCP server like foo2, that MCP server should remain available.

// .app.json
{
  "apps": {
    "foo": {
      "id": "connector_abc"
    }
  }
}

// .mcp.json
{
  "mcpServers": {
    "foo": {
      "url": "https://mcp.foo.com/mcp"
    },
    "foo2": {
      "url": "https://mcp.foo2.com/mcp"
    }
  }
}

Stack

• PR1: [codex] Add auth mode to plugin manager constructor #27652 seed plugin manager auth at construction.
• PR2: [codex] Gate plugin MCP servers by auth route #27459 route plugin surfaces by auth mode.
• PR3: [codex] Dedupe plugin MCPs by app declaration name #27607 dedupe plugin MCP servers by App declaration name.
• PR4: [codex] Preserve plugin apps in connector listings #27602 preserve plugin Apps in connector listings.
• PR5: [codex] Skip plugin MCP OAuth for matching app routes #27461 skip install-time plugin MCP OAuth for matching App routes.

Summary

• Preserve App declaration names in loaded plugin metadata.
• Keep public effective App outputs as deduped connector IDs for existing callers.
• For ChatGPT/SIWC, suppress only plugin MCP servers whose names match declared App names.

Validation

cargo fmt --all
cargo test -p codex-core-plugins plugin_auth_projection
cargo test -p codex-core-plugins effective_apps
cargo test -p codex-core-plugins read_plugin_for_config_installed_git_source_reads_from_cache_without_cloning
cargo test -p codex-core explicit_plugin_mentions_use_apps_for_chatgpt_dual_surface_plugins
cargo test -p codex-core explicit_plugin_mentions_keep_non_conflicting_mcp_for_chatgpt_auth
cargo test -p codex-app-server --test all plugin_install_filters_disallowed_apps_needing_auth
git diff --check

[felixxia-oai]

@codex review

[chatgpt-codex-connector]

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[xl-openai]

@codex review again

[chatgpt-codex-connector]

💡 Codex Review

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Reviewed commit: af36612242

ℹ️ About Codex in GitHub

Your team has set up Codex to review pull requests in this repo. Reviews are triggered when you

• Open a pull request for review
• Mark a draft as ready
• Comment "@codex review".

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