docs(kyberforge): fix remaining PR #91 review findings, add apm install routing

Re-review (comment 24) of fix commit e16c3dc found six new issues, mostly
introduced by that fix commit itself: a dangling reference to a Hard Rule
bullet the same commit deleted (apm-orchestrate.md/.agent.md Process step
2 still named "secret indirection"), and an ADR-0015 Decision bullet that
claimed "this ADR does not update CONTEXT.md" while the same commit had
just added a forward-pointer sentence to CONTEXT.md's Plugin/Plugin
marketplace entries. Both reworded to match what actually happened.

apm-install's APM_INSTALL_DIR escape-hatch example dropped the curl pipe
entirely (`APM_INSTALL_DIR=... sh` with nothing piped into it) — fixed in
both apm-install/SKILL.md and the installation.md research doc, verified
against the upstream Microsoft APM docs via Context7.

Neither apm-workflow nor apm-orchestrate routed to plain `apm install
[PACKAGE_REF]`, the CLI command that actually resolves/fetches
dependencies declared in apm.yml — apm-install only bootstraps the apm
binary/runtime, not per-package deps. Added a 5th "install" dispatch
action to apm-workflow (new references/install.md, SKILL.md table row,
README usage/files sync, sources.md provenance entry) and a matching
"install" operation group on apm-orchestrate so it can route there.

configure.md's apm.yml schema block was also missing the "legacy singular
`target:` CSV form is still accepted" caveat its sibling research doc
documents for the same field — added for consistency.

The sixth finding (paired .md/.agent.md Output-contract disagreement) was
checked against git-orchestrate and gitea-orchestrate's existing pairs and
found to match established repo convention (JSON schema in .md, prose
summary without the enum in .agent.md) — left unchanged as a false
positive rather than "fixed."

kyberforge bumped 1.3.0 -> 1.3.1 via agent-author's normal improve flow.

Refs: #91

Co-Authored-By: Claude Sonnet 5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_0186ERbyACLRuRxPRnqwpa4m

docs/adr/0015-apm-replaces-plugin-marketplace-authoring.md

@@ -44,8 +44,9 @@ new hand-maintained manifest format.
 - Actually translating the existing plugins into `apm.yml` + `.apm/` and running the real
   conversion is deferred to issue #90
   (https://git.dev.rkdr.net/Defame1297/holocron/issues/90).
-- `CONTEXT.md`'s "Plugin"/"Skill"/"Plugin marketplace" glossary entries remain accurate as
-  written until issue #90 actually executes — this ADR does not update them.
+- `CONTEXT.md`'s "Plugin"/"Plugin marketplace" glossary entries get a forward-pointer to this
+  ADR so a session-start read surfaces the pending change; their substantive definitions remain
+  accurate until issue #90's conversion actually executes — this ADR does not rewrite them.
 
 ## Considered options