chore(a2ml): remove 8 deprecated legacy-Scheme example dups (Item 10/Day 9)

The 6 machine-readable metadata formats canonically use S-expression
A2ML with the .a2ml extension (see 0-AI-MANIFEST.a2ml invariant). The
agentic/meta/neurosym/playbook example dirs each carried a stale
{minimal,comprehensive}.scm that self-declares "DEPRECATED ... legacy
Guile Scheme (.scm)" and points at its already-present .a2ml sibling.

Delete the 8 deprecated .scm dups (every one has a verified, non-trivial
.a2ml counterpart) and repoint the two README.adoc link lists
(meta-a2ml, playbook-a2ml) from examples/*.scm to examples/*.a2ml so no
doc links break.

Scope policy (re-derived 2026-05-17; plan's ~22-file estimate was
unreproducible — true estate scope ~325 .machine_readable/*.scm, all
downstream): canonical/template-first. PRESERVE untouched: guix.scm /
channels / manifest, tree-sitter queries, executable (define-module)
Guile, and .scm-suffixed satellite/repo path names. The downstream
.machine_readable/*.scm rename tail is staged and deferred.

Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>

Author: hyperpolymath

meta-a2ml/README.adoc

@@ -213,8 +213,8 @@ The formal specification is in the `spec/` directory:
 
 See the link:examples/[examples/] directory:
 
-* link:examples/minimal.scm[minimal.scm] - Minimal valid META file
-* link:examples/comprehensive.scm[comprehensive.scm] - Full-featured example
+* link:examples/minimal.a2ml[minimal.a2ml] - Minimal valid META file
+* link:examples/comprehensive.a2ml[comprehensive.a2ml] - Full-featured example
 
 == Integration with STATE.a2ml
 

playbook-a2ml/README.adoc

@@ -216,8 +216,8 @@ The formal specification is in the `spec/` directory:
 
 See the link:examples/[examples/] directory:
 
-* link:examples/minimal.scm[minimal.scm] - Minimal valid PLAYBOOK
-* link:examples/comprehensive.scm[comprehensive.scm] - Full-featured example
+* link:examples/minimal.a2ml[minimal.a2ml] - Minimal valid PLAYBOOK
+* link:examples/comprehensive.a2ml[comprehensive.a2ml] - Full-featured example
 
 == Conformance Requirements