fix(1.2.x): backport codespell-detected spelling corrections to 1.2.x branch

[somethingwithproof]

Summary

Backport the spelling corrections from #6803 (develop branch) to the 1.2.x maintenance branch.

codespell scan of upstream/1.2.x identified the same 79 spelling errors in Cacti-owned PHP, shell, and XML source files. The 1.2.x codebase diverges from develop at the library level, so a separate backport PR is required.

Type

• Fix (spelling correction — no logic change)
• Backport

Base Branch

1.2.x

Detection Method

codespell \
  --skip=".git,include/vendor,include/fa,*.min.js,*.min.css,*.po,*.pot,CHANGELOG,include/js/Chart.js,include/js/d3.js" \
  --ignore-words-list="parms,parm,tht,ot,CurrOS,hasTables,pring,realy,realx,wheight,alues,alue" \
  --quiet-level=2

Files Affected (79 corrections across 26 files)

Same file set as #6803, plus lib/reports.php:1541 and tree.php:204 which are unique to 1.2.x:

• auth_changepassword.php, automation_networks.php, cactid.php
• cli/audit_database.php, cli/batchgapfix.php, cli/change_device.php
• cli/rebuild_poller_cache.php, cli/repair_database.php, cli/splice_rrd.php
• cli/update_heartbeat.php, data_queries.php, graphs.php
• include/global_arrays.php, include/global_languages.php, include/global_settings.php
• install/upgrades/1_0_0.php, install/upgrades/1_1_11.php, install/upgrades/1_1_20.php
• install/upgrades/1_2_19.php
• lib/api_aggregate.php, lib/api_automation.php, lib/api_device.php, lib/api_graph.php
• lib/auth.php, lib/boost.php, lib/database.php, lib/functions.php
• lib/html_tree.php, lib/html_utility.php, lib/installer.php, lib/poller.php
• lib/reports.php, lib/rrd.php, lib/rrdcheck.php, lib/utility.php
• poller_boost.php, poller_dsstats.php, poller_realtime.php, poller_rrdcheck.php
• tree.php

Testing

All edits are in comments, docblocks, and string literals. No logic changes. No PHP parse errors.

Refs #6803