fix(mise): auto-install minimum version configured in mise.toml

[malept]

What this PR does / why we need it

When min_version.hard is set in a project's mise.toml, ensure_mise_installed now automatically upgrades mise if the installed version is below the configured minimum. This prevents CI failures and confusing errors when a project requires a newer mise version than what's installed on the worker.

Also:

• Refactors version checking into reusable mise_version() and mise_version_compatible() functions, replacing the previous gojq-based parsing (which could fail if mise was too old to run the project config)
• Fixes a pre-existing bug where wc -c output included the filename, breaking the empty-file check for the cached install script
• Moves ensure_mise_installed before bootstrap_github_token in setup.sh so mise is available at the very start of CI setup

Jira ID

DT-5166

Notes for your reviewers

• If min_version.hard is not set in mise.toml (the current default), behavior is unchanged
• install_mise now accepts an optional version parameter; the apt fallback cannot install a specific version and will warn accordingly
• mise_version() deliberately avoids JSON+gojq since gojq is mise-installed and may not be available when the installed mise is too old for the project config due to chicken-and-egg dependencies

TODO

Note

This is a draft because it depends on #1110. It should be reviewable otherwise.

• Merge fix(ci): reduce network calls on machine workers #1110
• Rebase on main

---

Rovo Dev code review: Out of Rovo Dev credits
You've used all your Rovo Dev credits, so Rovo Dev can't review your pull requests.

[getoutreach-ci-1]

Link to code coverage report (posted by coverbot 🤖)