fix: walk up directory tree to find manifest.json

[mdbraber]

Summary

• Instead of only looking for manifest.json in process.cwd(), walk up the directory tree until a valid Obsidian plugin manifest is found (identified by having an id field)
• Silently return null when no manifest is found, removing the console.error that fires in monorepo setups
• Existing behavior is preserved: when no manifest is found, isDesktopOnly rules default to the safer option (Node.js imports disallowed, no Node globals)

Motivation

In monorepo setups (e.g., pnpm workspaces with Turborepo), ESLint often runs from the workspace root or a sub-package directory — neither of which contains manifest.json. The current code logs a noisy console.error("Failed to load JSON file:", err) every time, even though this is expected and harmless.

The walk-up approach mirrors how tools like ESLint itself find config files — start at cwd and check each parent directory. The id field check ensures we only match actual Obsidian plugin manifests, not unrelated manifest.json files (e.g., Chrome extensions).

Test plan

• Existing 274 tests pass without modification
• Verify in a monorepo where manifest.json is in a parent directory
• Verify in a standard single-package setup (manifest.json in cwd — same behavior as before)
• Verify no console.error output when manifest.json is absent

🤖 Generated with Claude Code

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[mdbraber]

I have read the CLA Document and I hereby sign the CLA

[joethei]

I don't like how this walks up the directory tree indefinitely, there should be a limit.

[mdbraber]

@joethei what would be reasonable limit? if we consider monorepo package structure I would say 2 or 3 would suffice? Or should it be configurable?