ansible: entry-list play bodies + ansible-applier

[polyedre]

Summary

Rework the Ansible surface so an inventory reads as a list of declarations, with functions reserved for sugar and control flow.

• One entry grammar for every play-body form (tasks, as, each, only, handlers):
  • ("Name" (module (arg val) …) #:keyword val …) declares a task, in YAML order (name, module dict, task-level keywords).
  • An entry whose head is a symbol is a Scheme expression whose task(s) splice in, so helpers drop in where repetition earns them.
  • Bare module symbols resolve to ansible.builtin.<module>; dotted names are taken as written.
• as is now a body form taking a bare user symbol ((as root …)), still nesting with innermost-wins.
• each/only replace map/if plumbing; task remains for a single task outside a body.
• Removes the task/handler record macros, the as procedure and the example's local cat/tasks/copy helpers.
• examples/ansible.scm rewritten as one declaration list per host (358 → 227 lines); rendered playbook is byte-identical to before except that task-level keys (when, register) now follow the module dict.
• Docs and CHANGELOG updated; two checks for the grammar added to test.scm.

Applier: hexol apply runs ansible-playbook

• ansible-applier #:inventory (path | state alist) writes deploy/playbook.json and deploy/inventory.json (state alist converted to Ansible all/hosts/children shape) and runs ansible-playbook -i INV PB …. --dry-run maps to --check --diff; hexol diff is refused (ansible has no drift exit code).
• hexol apply passes the first flag it does not own, and everything after it, to the appliers via the new applier-args parameter:

  hexol apply -i examples/ansible.scm --list-tasks --limit web1.acme.example
  

• examples/ansible.scm registers (appliers ("ansible" (ansible-applier #:inventory inv))).
• Drops the tracked deploy/golden/ files: deploy/ is generated output and already gitignored.

Test plan

• make build
• guile -L . test.scm — all checks passed (new ansible checks included)
• make test-examples — all example renders passed
• guile -L . test/apply-mode.scm — ansible applier checks (PATH shim) pass
• guix shell ansible -- ./bin/hexol apply -i examples/ansible.scm --list-tasks --limit web1.acme.example lists play CI: provision from manifest.scm via Guix #1 only
• hexol render -o ansible -i examples/ansible.scm diffed against pre-change output: identical modulo key order noted above
• make test in full fails locally on test/import.scm (Unbound variable: make-yaml_parser_t, libyaml FFI missing in this environment) — pre-existing, unrelated

🤖 Generated with Claude Code