fix(monitor): detect updates started with the u short alias

[borzaka]

Description

fn_monitor_check_update in lgsm/modules/command_monitor.sh skips monitoring when lock/update.lock exists and an update process is running. It finds the update process with pgrep -fcx against the command lines update, validate, v, force-update, fu, update-restart and ur, but not u, although core_getopt.sh defines the update command as cmd_update=("u;update" ...).

Because pgrep -x needs an exact match, an update started with ./gameserver u is not found and monitor carries on. During a SteamCMD update that stops the server, the stop keeps ${selfname}-monitoring.lock (the first command is UPDATE, not STOP). So the next monitor run reports Checking session: FAIL, sends a monitor-session alert and runs command_restart.sh while SteamCMD is still updating the server.

This PR adds the missing "/bin/bash ./${selfname} u" check next to the update check. Only lgsm/modules/command_monitor.sh is changed.

Fixes #4997

Type of change

• Bug fix (a change which fixes an issue).
• New feature (a change which adds functionality).
• New Server (new server added).
• Refactor (restructures existing code).
• Comment update (typo, spelling, explanation, examples, etc).

Testing

Please list the exact validation you performed and the outcome.

• Commands/tests run:

  • Extracted fn_monitor_check_update from both develop (28b1d67) and this branch, stubbed the print/log helpers and core_exit.sh, and ran it with update.lock present while a real /bin/bash ./testserver <command> process was running, for every update related command.
  • Ran the same check with no matching process, and with update.lock missing.
  • Checked for false positives with /bin/bash ./testserver ul, update-lgsm, uf and u extra running.
  • bash -n lgsm/modules/command_monitor.sh and shellcheck 0.11.0 with the repository's .shellcheckrc.
  • Not run: a full update and monitor cycle on an installed game server.

• Result:

  Running command	develop	This branch
  update	skip (update detected)	skip (update detected)
  u	monitor continues	skip (update detected)
  validate, v, force-update, fu, update-restart, ur	skip (update detected)	skip (update detected)
  lock present, no update process	monitor continues	monitor continues
  u running, no lock	monitor continues	monitor continues
  ul, update-lgsm, uf, u extra running, lock present	monitor continues	monitor continues

  No bash -n or shellcheck findings.

• Environment used (distro/version): Ubuntu 22.04.5 LTS, bash 5.1.16, procps-ng 3.3.17.

Risk and rollback

• Risk level: low. One more exact-match pgrep check in an existing condition; other commands and the stale lockfile handling are unchanged.
• Rollback plan: revert this commit.

Breaking changes

• No breaking changes.
• Breaking changes included (describe below).

Documentation impact

• No documentation update required.
• User documentation update required.
• Developer documentation update required.

Checklist

PR will not be merged until all steps are complete.

• This pull request links to an issue.
• This pull request uses the develop branch as its base.
• This pull request subject follows the Conventional Commits standard.
• This code follows the style guidelines of this project.
• I have performed a self-review of my code.
• I have provided a detailed enough description of this PR.

Documentation

If documentation does need updating either update it by creating a PR (preferred) or request a documentation update.

• User docs: https://github.com/GameServerManagers/LinuxGSM-Docs
• Dev docs: https://github.com/GameServerManagers/LinuxGSM-Dev-Docs

Thank you for your Pull Request!

🤖 Generated with Claude Code

[dgibbs64]

Thanks @borzaka, and sorry: I merged #5002 with exactly this change without spotting that you'd already opened this PR (and #5000) for the issue you reported. Closing it as covered by #5002. You'll be credited for both fixes in the v26.3.0 release notes.