Bug: modlens fails in DSH Desktop Electron app — process.execPath is Electron binary, not node

[yeruizhi]

Bug Report

Environment: DeepSeek Harness (DSH) Desktop Electron app on macOS
modlens version: 3.10.0
DSH profile: @liustack/modlens/dsh loaded via cordis patch

What happens

When pasting an image into the DSH Desktop Electron app, modlens reports:

A pasted image could not be read by modlens: error: too many arguments for 'analyze'. Expected 0 arguments but got 1.

The same paste works perfectly in the DSH web dev instance (node process, port 3080).

Root cause

In dsh/index.js, both read_image.execute() and the paste-unlock readImageBlock() spawn the CLI with:

run(process.execPath, [cli, '-i', file, '--timeout', String(CLI_TIMEOUT_MS)], signal)

In the Electron desktop app, process.execPath is the Electron binary (DeepSeek Harness.app/Contents/MacOS/DeepSeek Harness), not node. When Electron spawns itself with [dist/main.js, '-i', <path>, ...], it consumes/reorders the -i flag as an Electron/Chromium switch. Commander then sees <path> as a positional argument to the default analyze command and throws:

error: too many arguments for 'analyze'. Expected 0 arguments but got 1.

Reproduction

# Works (node):
node dist/main.js -i /path/to/image.jpg --timeout 180000   # ✅ returns JSON

# Fails (Electron binary = DSH desktop app's process.execPath):
/Applications/DeepSeek\ Harness.app/Contents/MacOS/DeepSeek\ Harness dist/main.js -i /path/to/image.jpg --timeout 180000
#  error: too many arguments for 'analyze'. Expected 0 arguments but got 1.

Suggested fix

Use a fixed node path instead of process.execPath:

// Option A: resolve node from PATH or use env override
const NODE_BIN = process.env.MODLENS_NODE ?? process.execPath;
run(NODE_BIN, [cli, '-i', file, '--timeout', String(CLI_TIMEOUT_MS)], signal);

Or detect Electron at runtime:

const isElectron = typeof process !== 'undefined' && process.versions?.electron != null;
const runner = isElectron ? 'node' : process.execPath;
run(runner, [cli, '-i', file, '--timeout', String(CLI_TIMEOUT_MS)], signal);

Both execute() (the read_image tool) and readImageBlock() (paste unlock) need this fix.

Workaround for users

Run DSH in Chrome (npx @deepseek-ai/dsh web) instead of the Desktop Electron app — there process.execPath is node and modlens works correctly.