docs(skills): stop routing content at the README this branch deleted

skill-author still told authors to move description overflow "to the
body or to README.md" while this branch deleted every per-skill
README.md, every references/README.md and the README scaffold template.
factory-audit's skill-file-structure.md bans non-spec files at the
skill root, and the line that used to carve README out of that rule
went with them. So skill-author created the file, factory-audit failed
it, and nothing read it. 8ce5392 fixed the two scripts and missed the
reference prose.

The two contract.md files now differ deliberately: a skill's overflow
goes to the body or a references/ file, an agent's to the body alone,
because an agent is a single file with no references/ directory to
disclose to. agent-description-quality.md's "the plugin's README.md" is
left alone, plugin READMEs being the ones that survive.

Deleting retrofit.md also dropped three instructions baa2f5d did not
restore with the cut list, two of which retrofit.md itself recorded as
having no validator behind them: re-cite sources.md's Contributing
files after content moves, since validate-provenance exits 0 on exactly
that drift, and re-check a relocated gate's reachability, since a
Gotcha moved into one flow's file is invisible to the others and the
word counts improve either way. The third is that boundary clauses are
plural — contract.md read as a cap where git-remotes carries four.

Also: contract.md named an unqualified scripts/validate.sh that does
not exist in skill-author, which skill-file-structure.md calls a hard
error; and agent-body-and-delegation.md's simile pointed at a stale
README row as the characteristic skill defect, a defect class that can
no longer occur, replaced with a SKILL.md naming a references/ file
that is not there.

skill-author 1.0.4, agent-author 1.0.3, factory-audit 1.0.2.

Co-Authored-By: Claude Opus 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01NwD8Egs5r4ndqeFLmhusX2

plugins/kyberforge/.apm/skills/factory-audit/references/agent-body-and-delegation.md

@@ -44,7 +44,8 @@ A plugin-scope agent is a single `.apm/agents/<name>.agent.md` file with no sibl
 directory. It cannot progressively disclose to itself — it can only delegate to skills. So a
 procedure spelled out in an agent body that a skill the agent invokes already owns is not a
 shortcut: it is a second copy of that procedure, and the second copy drifts. This is the
-characteristic agent defect, the way a stale README row is the characteristic skill defect.
+characteristic agent defect, the way a `SKILL.md` naming a `references/` file that is not there is
+the characteristic skill defect.
 
 **An agent body that restates a procedure owned by a skill it can invoke is a FAIL.** The Fix is
 always the same shape: invoke `<skill>` instead.

plugins/kyberforge/.apm/skills/factory-audit/references/skill-description-quality.md

@@ -46,7 +46,7 @@ A model-invoked description carries exactly three things:
    instead") is only a SUGGESTION unless a second target in the same sentence resolves. Take the
    script's tier as given and report it once, under Structure.
 
-Everything else belongs in the body or in `README.md`.
+Everything else belongs in the body or in a `references/` file.
 
 ## Indirect triggers — conditional, never blanket