fix(desktop): restore managed Node server startup (#348)

## Summary
- revert the Bun standalone desktop packaging path and restore the
server's original `dist/bin.js` bootstrap flow
- add a managed Node runtime for Electron and Tauri that downloads only
the current platform/arch artifact into `~/.config/codenomad`
- update desktop startup and packaging scripts so packaged apps use the
managed runtime consistently, and clean up Electron's expected
navigation-abort log noise

## Testing
- npm run typecheck --workspace @neuralnomads/codenomad-electron-app
- cargo check
- npm run build --workspace @neuralnomads/codenomad
- npm run build:mac --workspace @neuralnomads/codenomad-electron-app
- launch
`packages/electron-app/release/mac-arm64/CodeNomad.app/Contents/MacOS/CodeNomad`
and verify the packaged server reaches ready with the managed Node
runtime

packages/server/scripts/copy-opencode-config.mjs

@@ -1,6 +1,6 @@
 #!/usr/bin/env node
 import { spawnSync } from "child_process"
-import { cpSync, existsSync, mkdirSync, readdirSync, rmSync } from "fs"
+import { cpSync, existsSync, mkdirSync, rmSync } from "fs"
 import path from "path"
 import { fileURLToPath } from "url"
 
@@ -14,67 +14,6 @@ const selfLinkDir = path.resolve(nodeModulesDir, "@codenomad", "opencode-config"
 const npmExecPath = process.env.npm_execpath
 const npmNodeExecPath = process.env.npm_node_execpath
 
-function stripNodeModuleBins(rootDir) {
-  const root = path.join(rootDir, "node_modules")
-  if (!existsSync(root)) {
-    return 0
-  }
-
-  const stack = [root]
-  let removed = 0
-
-  while (stack.length > 0) {
-    const current = stack.pop()
-    if (!current) break
-
-    let entries
-    try {
-      entries = readdirSync(current, { withFileTypes: true })
-    } catch {
-      continue
-    }
-
-    for (const entry of entries) {
-      const full = path.join(current, entry.name)
-      if (entry.name === ".bin") {
-        rmSync(full, { recursive: true, force: true })
-        removed += 1
-        continue
-      }
-
-      if (entry.isDirectory()) {
-        stack.push(full)
-      }
-    }
-  }
-
-  return removed
-}
-
-function stripOptionalNativeAddons(rootDir) {
-  const nodeModulesRoot = path.join(rootDir, "node_modules")
-  if (!existsSync(nodeModulesRoot)) {
-    return 0
-  }
-
-  const removablePaths = [
-    path.join(nodeModulesRoot, "@msgpackr-extract"),
-    path.join(nodeModulesRoot, "msgpackr-extract"),
-  ]
-
-  let removed = 0
-  for (const targetPath of removablePaths) {
-    if (!existsSync(targetPath)) {
-      continue
-    }
-
-    rmSync(targetPath, { recursive: true, force: true })
-    removed += 1
-  }
-
-  return removed
-}
-
 if (!existsSync(sourceDir)) {
   console.error(`[copy-opencode-config] Missing source directory at ${sourceDir}`)
   process.exit(1)
@@ -119,14 +58,4 @@ rmSync(targetDir, { recursive: true, force: true })
 mkdirSync(path.dirname(targetDir), { recursive: true })
 cpSync(sourceDir, targetDir, { recursive: true })
 
-const removedBins = stripNodeModuleBins(targetDir)
-if (removedBins > 0) {
-  console.log(`[copy-opencode-config] Removed ${removedBins} node_modules/.bin directories`)
-}
-
-const removedNativeAddons = stripOptionalNativeAddons(targetDir)
-if (removedNativeAddons > 0) {
-  console.log(`[copy-opencode-config] Removed ${removedNativeAddons} optional native addon package paths`)
-}
-
 console.log(`[copy-opencode-config] Copied ${sourceDir} -> ${targetDir}`)