Check minimum system requirements during server install

[phinze]

Mary managed to install miren on a 512 MB server, which happily accepted the install and then promptly died during a deploy. The installer had no guardrails — it checked for root and systemd but never looked at whether the machine could actually run everything.

We already document minimum requirements in the getting-started guide (4 GB memory, 50 GB storage), so this wires those thresholds into the install flow right after the existing prerequisite checks. If you're below the minimums, the install stops with a clear message explaining what's needed and links to the docs. If you're in the "it'll probably work but we wouldn't recommend it" zone (between minimum and recommended), you get a warning but things keep moving.

For unusual environments where we can't read /proc/meminfo or stat the filesystem, we warn but don't block — no sense locking someone out just because their system is weird. And --skip-system-check is there for anyone who knows what they're doing and wants to push through anyway.

While we were at it, we moved the system requirements docs out of a buried anchor in getting-started and onto their own reference page, so the CLI has something stable to link to and users can actually find it. Also added a note to CLAUDE.md about the correct docs URL (miren.md, not miren.dev/docs) since we keep getting that wrong.

Only applies to the systemd (bare metal) install path for now — Docker installs are a different story.

Closes MIR-748

[coderabbitai]

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📥 Commits

Reviewing files that changed from the base of the PR and between e537cee and b183017.

📒 Files selected for processing (7)

• CLAUDE.md
• cli/commands/server_install.go
• cli/commands/server_install_other.go
• cli/commands/server_install_test.go
• docs/docs/getting-started.md
• docs/docs/system-requirements.md
• docs/sidebars.ts

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📝 Walkthrough

Walkthrough

This pull request implements system requirements validation for server installation. Changes include adding memory and disk space checks in the install workflow with a new --skip-system-check flag to bypass validation. New functions detect available resources, emit guidance warnings, and determine if minimum requirements are met. The ServerInstall options struct is updated with the SkipSystemCheck field across multiple files. Test coverage validates the system requirements guidance logic across various resource scenarios. Documentation is restructured: a detailed system requirements page is added and referenced in sidebars, while redundant content is removed from getting-started.

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