also show me the results of git remote -v
is your git copy of a fork you might have made?

then u do a git pull to get the latest
then npm install
then npm install in any module folder that has a package.json file

snowboy (MMM-voice and MMM-Hotword) is a pain in the rear…
usually requires a special command (electron-rebuild) to rebuild some part at the new electron level…
see instructions in MMM-Hotword

after doing the git pull in the MM folder
you then
did npm install while in the MM folder, right? you must

as you have MMM-voice installed
u need to do npm install there too

pi@raspberrypi:~/MagicMirror $ npm start &
[1] 1486
pi@raspberrypi:~/MagicMirror $ 
> magicmirror@2.6.0 start /home/pi/MagicMirror
> sh run-start.sh

Starting MagicMirror: v2.6.0
Loading config ...
Loading module helpers ...
No helper found for module: MMM-pages.
No helper found for module: MMM-page-indicator.
Initializing new module helper ...
Module helper loaded: MMM-Remote-Control-Repository
No helper found for module: alert.
Initializing new module helper ...
Module helper loaded: MMM-Remote-Control
No helper found for module: clock.
WARNING! Could not load config file. Starting with default configuration. Error found: Error: Cannot find module 'lmtool'
Loading module helpers ...
No helper found for module: MMM-pages.
No helper found for module: MMM-page-indicator.
Initializing new module helper ...
Module helper loaded: MMM-Remote-Control-Repository
No helper found for module: alert.
Initializing new module helper ...
Module helper loaded: MMM-Remote-Control
No helper found for module: clock.
App threw an error during load
Error: Cannot find module 'lmtool'
    at Module._resolveFilename (internal/modules/cjs/loader.js:602:15)
    at Function.Module._resolveFilename (/home/pi/MagicMirror/node_modules/electron/dist/resources/electron.asar/common/reset-search-paths.js:35:12)
    at Function.Module._load (internal/modules/cjs/loader.js:528:25)
    at Module.require (internal/modules/cjs/loader.js:658:17)
    at require (internal/modules/cjs/helpers.js:20:18)
    at Object.<anonymous> (/home/pi/MagicMirror/modules/MMM-voice/node_helper.js:32:16)
    at Object.<anonymous> (/home/pi/MagicMirror/modules/MMM-voice/node_helper.js:373:3)
    at Module._compile (internal/modules/cjs/loader.js:711:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:722:10)
    at Module.load (internal/modules/cjs/loader.js:620:32)
Whoops! There was an uncaught exception...
{ Error: Cannot find module 'lmtool'
    at Module._resolveFilename (internal/modules/cjs/loader.js:602:15)
    at Function.Module._resolveFilename (/home/pi/MagicMirror/node_modules/electron/dist/resources/electron.asar/common/reset-search-paths.js:35:12)
    at Function.Module._load (internal/modules/cjs/loader.js:528:25)
    at Module.require (internal/modules/cjs/loader.js:658:17)
    at require (internal/modules/cjs/helpers.js:20:18)
    at Object.<anonymous> (/home/pi/MagicMirror/modules/MMM-voice/node_helper.js:32:16)
    at Object.<anonymous> (/home/pi/MagicMirror/modules/MMM-voice/node_helper.js:373:3)
    at Module._compile (internal/modules/cjs/loader.js:711:30)
    at Object.Module._extensions..js (internal/modules/cjs/loader.js:722:10)
    at Module.load (internal/modules/cjs/loader.js:620:32) code: 'MODULE_NOT_FOUND' }
MagicMirror will not quit, but it might be a good idea to check why this happened. Maybe no internet connection?
If you think this really is an issue, please open an issue on GitHub: https://github.com/MichMich/MagicMirror/issues
Launching application.

pi@raspberrypi

but u have to start in MagicMirror folder

cd ~/MagicMirror
npm start &

npm start &
[1] 1352
pi@raspberrypi:~ $ npm ERR! path /home/pi/package.json
npm ERR! code ENOENT
npm ERR! errno -2
npm ERR! syscall open
npm ERR! enoent ENOENT: no such file or directory, open '/home/pi/package.json'
npm ERR! enoent This is related to npm not being able to find a file.
npm ERR! enoent 

npm ERR! A complete log of this run can be found in:
npm ERR!     /home/pi/.npm/_logs/2019-04-02T22_38_46_083Z-debug.log

npm WARN MMM-pages No repository field.
npm WARN MMM-pages No license field.

package.json doesn’t have some typically useful fields… no problems

so, one thing to try also is

npm start &

which will start MM AND give u back the terminal window…

I get lots of messages as things start up there…

npm WARN MMM-pages No repository field.
npm WARN MMM-pages No license field.

audited 275 packages in 6.448s
found 0 vulnerabilities

and this from mmm-hue-lights and a couple of others

npm WARN saveError ENOENT: no such file or directory, open '/home/pi/MagicMirror/modules/package.json'
npm WARN enoent ENOENT: no such file or directory, open '/home/pi/MagicMirror/modules/package.json'
npm WARN modules No description
npm WARN modules No repository field.
npm WARN modules No README data
npm WARN modules No license field.

audited 1 package in 1.465s
found 0 vulnerabilities

What errors. Let’s work thru ut

Mm is short for MagicMirror

pi@raspberrypi:~ $ npm start dev

you need to

cd MagicMirror

THEN do the

npm start dev