fix(config): avoid dedup collisions for file:// plugins in node_modules

[cyberprophet]

Issue for this PR

Closes #15591
Related: #10115

Type of change

• Bug fix
• New feature
• Refactor / code improvement
• Documentation

What does this PR do?

Config.getPluginName() previously identified file:// plugins by filename only (e.g. index).
When npm plugins are resolved to .../node_modules/<pkg>/dist/index.js, different plugins collapsed to the same identity and only the last plugin survived deduplication.

This PR updates plugin identity extraction to:

• detect node_modules file URLs and use package identity (foo, @scope/pkg), not filename identity
• keep existing filename fallback for non-node_modules local plugins
• handle parsing in a cross-platform way so Windows test runners don't throw on synthetic POSIX-style file URLs

This directly matches the reproduction pattern reported in #10115 (order-dependent "only last plugin" behavior).

How did you verify your code works?

• bun test test/config/config.test.ts --test-name-pattern "extracts name from file:// URL|prefers local file over npm package with same name|extracts package name from node_modules file:// URL|keeps multiple npm plugins resolved as file:// URLs" ✅
• bun run typecheck ✅

Also addressed CI feedback:

• Updated PR description to match required template sections (issue-compliance action)
• Fixed Windows CI failures caused by fileURLToPath() throwing for POSIX-like file URLs in tests

Screenshots / recordings

N/A (non-UI change)

Checklist

• I have tested my changes locally
• I have not included unrelated changes in this PR

[github-actions]

The following comment was made by an LLM, it may be inaccurate:

I found one potentially related PR:

PR #8758: "fix: use full URL for file:// plugin deduplication"
#8758

This PR appears to address a similar issue with file:// plugin deduplication. It may be related to or a predecessor of the current PR #15598, as both deal with preventing false deduplication collisions for file:// plugins. However, PR #15598 specifically targets the Config.getPluginName() function and package identity extraction from node_modules, which may be a more targeted fix or a different approach to the same problem.

You should verify if PR #8758 is already merged or if the current PR is intended to supersede it.

[github-actions]

Thanks for updating your PR! It now meets our contributing guidelines. 👍

[cyberprophet]

Addressed the automation feedback in this update:

• Rewrote PR description to match the required template sections (Issue, Type of change, What does this PR do, Verification, Checklist)
• Added explicit linkage to [Bug]: Only the last plugin loads in OpenCode 1.1.32 - Multiple plugins not supported #10115 as related reproduction context
• Pushed a follow-up fix for Windows CI: avoid fileURLToPath() throwing on POSIX-style file URLs while preserving node_modules package identity dedup behavior

Latest commit: 0ee3a2e