Local dev failing with "unusual" components (e.g: css only component, multiple js files in the same component)

[SuperPluck]

Summary

While trying to launch an Experience Site, I having multiple errors that prevent usage. Two examples so far are:

1. Components that are css only: the server launch fails with ServerError: An unexpected error occurred: "ENOENT: no such file or directory, open 'C:\Workspace\pbs\force-app\main\default\lwc\mycomponent\mycomponent.js' (Note: I can bypass this by adding an empty js file)
2. Components that have multiple js files and import elements from them (import { Builder } from './builder';): server launch fails with LWR Diagnostic Error: An unexpected error occurred: "ENOENT: no such file or directory, open 'C:\Workspace\pbs\force-app\main\default\lwc\mycomponent\builder'

Additional Information

Screenshots:

Logs:

System Information

SF CLI: @salesforce/cli/2.70.7 win32-x64 node-v20.11.0
Plugin version: prerelease
Terminal: git bash

{
  "architecture": "win32-x64",
  "cliVersion": "@salesforce/cli/2.70.7",
  "nodeVersion": "node-v20.11.0",
  "osVersion": "Windows_NT 10.0.26100",
  "rootPath": "C:\\Users\\Fernando Gavinho\\AppData\\Roaming\\npm\\node_modules\\@salesforce\\cli",
  "shell": "C:\\Program Files\\Git\\usr\\bin\\bash.exe",
  "pluginVersions": [
    "@oclif/plugin-autocomplete 3.2.13 (core)",
    "@oclif/plugin-commands 4.1.13 (core)",
    "@oclif/plugin-help 6.2.19 (core)",
    "@oclif/plugin-not-found 3.2.30 (core)",
    "@oclif/plugin-plugins 5.4.22 (core)",
    "@oclif/plugin-search 1.2.17 (core)",
    "@oclif/plugin-update 4.6.17 (core)",
    "@oclif/plugin-version 2.2.17 (core)",
    "@oclif/plugin-warn-if-update-available 3.1.26 (core)",
    "@oclif/plugin-which 3.2.20 (core)",
    "@salesforce/cli 2.70.7 (core)",
    "apex 3.6.7 (core)",
    "api 1.3.2 (core)",
    "auth 3.6.80 (core)",
    "data 3.13.1 (core)",
    "deploy-retrieve 3.15.20 (core)",
    "info 3.4.27 (core)",
    "lightning-dev 2.8.0 (user) published 19 days ago (Thu Dec 19 2024) (latest is 1.10.0)",
    "limits 3.3.42 (core)",
    "marketplace 1.3.7 (core)",
    "org 5.2.9 (core)",
    "packaging 2.9.6 (core)",
    "schema 3.3.44 (core)",
    "settings 2.4.9 (core)",
    "sobject 1.4.46 (core)",
    "telemetry 3.6.27 (core)",
    "templates 56.3.33 (core)",
    "trust 3.7.50 (core)",
    "user 3.6.4 (core)"
  ]
}

OS: Windows

Experience Sites Only:

{
  "orgId": "00DPv000001Iw8D",
  "siteId": "0DMPv0000001Lf8",
  "clwrVersion": "254.159",
  "coreVersion": "254.2",
  "coreChangelist": "50901517",
  "bundleGenerationDate": "Jan 8, 2025 1:11:27 PM",
  "siteTemplateName": "talon-template-byo",
  "deployTarget": "CORE"
}

[SuperPluck]

Since I was not able to move past example 2, I can't say for sure, but I expect it might have problems with components that have multiple html templates too

[git2gus]

This issue has been linked to a new work item: W-17579988