[addadi]

What

Bind address was hardcoded to 127.0.0.1. This adds:

• Config.host JSON field (default 127.0.0.1; empty value falls back to default)
• --host <addr> CLI flag
• Precedence: CLI --host > config file host > default — mirrors the existing --port behavior
• Startup log / listen error messages now include the resolved host

Why

Multi-host and container deployments (e.g. reaching the server from another host or a container bridge) previously required a recompile to change the bind address. --port was already configurable; --host was the missing half.

Validation

• zig build clean
• zig build test green (new tests: default host, config-file host parse, host-unset keeps default)
• Manual run: nulltickets --host 127.0.0.2 --port 7799 binds and serves /health on the given address

No behavior change for existing deployments: without --host and without a config host key, the server still binds 127.0.0.1.

[vernonstinebaker]

Clean, minimal, and convention-consistent: host config field (default 127.0.0.1 — zero behavior change unless explicitly configured) + --host CLI override, matching nullboiler's flag style. Tests cover default, override, and unset cases. Note: this branch predates #9's test wiring, so its CI ran an empty suite — after merge, main's 18+ test suite covers it (and these host tests will actually execute for the first time). Merging.

[vernonstinebaker]

Merged — but heads-up: the textual auto-merge spliced this PR's new test onto #9's refactored test region in config.zig, leaving pre-0.16 tmp.dir.writeFile/realpathAlloc forms that broke the build on main (the PR's CI check predated #9, so the merge result never got re-validated — the empty-suite gap we documented). Repaired in a follow-up commit on main; 19/19 tests pass (18 from #9 + this PR's host-default test now actually running).