zabbix: bring agent, server, and proxy to parity

[danielfdickinson]

📦 Package Details

Maintainer: @danielfdickinson

Description:
Splits out the main set of changes from #30010 because it is cleaner / better separation of concerns.

• Use separate users for server and proxy. This is the upstream recommendation, and
  fits with our seperation of agent and server.
• Tweak the agentd and server patch configuration and bring agentd and
  server confgurations to parity.
• Tweak server initscript and bring agentd to parity
  • Genericize zabbix_server initscript.
  • Add shellcheck overrides where needed.
  • Add a 'never_root' config option (default true) that determines
    whether server starts as an unprivileged user or starts as root and
    drops to an unprivileged user (unless config is changed so it always
    runs as root).
  • Bring zabbix_agentd initscript to parity with zabbix_server for the
    initscript and configuration.
  • Tweak Makefile to reduce repetition
• Bring proxy to parity with server and agentd
  • Add config file patch for proxy
  • Add initscript for proxy
  • Update Makefile and support files to bring proxy to parity with
    agentd and server.

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• OpenWrt Version: OpenWrt SNAPSHOT r35362-9e43544bc6
• OpenWrt Target/Subtarget: bcm27xx/bcm2712
• OpenWrt Device: Raspberry Pi 5 Model B Rev 1.0

and (after split)

• OpenWrt Version: OpenWrt SNAPSHOT r35420-06c826e335
• OpenWrt Target/Subtarget: mediatek/filogic
• OpenWrt Device: OpenWrt One

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✅ Formalities

• I have reviewed the CONTRIBUTING.md file for detailed contributing guidelines.

If your PR contains a patch:

• It can be applied using git am
• It has been refreshed to avoid offsets, fuzzes, etc., using

  make package/<your-package>/refresh V=s

• It is structured in a way that it is potentially upstreamable
  N/A: OpenWrt-specific configuration tweaks

[openwrt-ai]

Reviewed 4 new commits; commit messages match their changes. One inline issue on the zabbix-agentd-basic conffiles/postinst references.

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Generated by Claude Code

[openwrt-ai]

Reviewed 2 new commits; no new issues found. The previously flagged zabbix-agentd-basic conffiles/postinst references now correctly point to Package/zabbix-agentd/* (hyphen), matching the actual defines.

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Generated by Claude Code