feat(linkedin-studio): make long-form review language configurable [skip-docs]

Wave 3 / Step 9 of the remediation plan (Phase 1 — usable by a non-author).

The long-form review layer shipped Norwegian-locked: language-reviewer graded
unconditional Norwegian, voice-scrubber's gold standard was 'approved Norwegian
editions', and the editorial/content craft gates pointed at a 'skrivekontrakt §C2'
that does not ship. A non-Norwegian adopter would get English prose graded against
Norwegian idiom and a gate that depends on an unshipped contract.

- config/edition-state.template.json: add additive 'language' field (top-level,
  default 'en') + a _doc entry. Threads into the language-dependent agents.
- agents/language-reviewer.md: new 'Language parameter' section — Norwegian-specific
  checks (anglicism->Norwegian idiom, kanselli-stil) apply only when language=='no';
  any other value grades that language's equivalents and never flags idiomatic
  English as an anglicism. Default 'en'.
- agents/voice-scrubber.md: gold standard reframed to 'approved editions in the
  configured language'; the Norwegian-chronicle calibration is the language=='no'
  instantiation.
- agents/editorial-reviewer.md + agents/content-reviewer.md: the in-tree checklist
  is now the operative, self-contained source of truth; Maskinrommet §C2 is an
  optional upstream contract that does NOT ship (available only on the author's
  runs). The gates work for an adopter without it.
- commands/newsletter.md: thread 'language' through the Step 6.5 cold-inputs and the
  per-reviewer call inputs; the writing contract is now 'if it ships'.

Norwegian remains fully working when language: no (the author's case).

fact-reviewer.md was in the plan's file list but needed no change on inspection:
its F1-F4 checks (claims/quotes/numbers/sources) are language-agnostic; its
'Norwegian' mentions are boundary notes vs language-reviewer, which stay correct.

[skip-docs]: three-doc + version reconciliation is Step 21 (pre-review-gate); these
intermediate Wave commits are not pushed before the /trekreview gate.

Verify: edition-state JSON parses + has top-level language 'en'; language-reviewer
has 'language ==' references and no unconditional-Norwegian assertion; editorial
§C2 reframed to in-tree fallback ('operative source', 'does not ship'); agent
fixtures 35/35 pass; structural lint exit 0 (61 passed).

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>

plugins/linkedin-studio/agents/editorial-reviewer.md

@@ -80,23 +80,23 @@ Two different roles, both necessary, neither sufficient alone. A persona PASS is
 **not** "ready for the editor" — it is "lands for the reader." This gate exists
 because those are not the same thing.
 
-## Truth source — the Maskinrommet writing-contract §C2
+## Truth source — the in-tree craft checklist (mirrors Maskinrommet §C2 when available)
 
-The checklist below is the **operationalized mirror of Maskinrommet
-skrivekontrakt §C2.** §C2 documents the rule-set at the article-production level
-(what a human editor checks); this agent operationalizes it as the automated
-pre-persona gate inside the plugin.
+The **operative source of truth is the two-axis checklist below.** It ships
+in-tree, is self-contained, and is everything you need to judge. It is the
+operationalized mirror of the author's **Maskinrommet skrivekontrakt §C2**, which
+documents the same rule-set at the article-production level (what a human editor
+checks). **§C2 itself does not ship with the plugin** (it lives in the author's
+series repo), so for any adopter the in-tree checklist *is* the contract — you do
+**not** need §C2 to run this gate.
 
-> **Mirror rule (bidirectional, cardinal).** §C2 is the source of truth. A change
-> on either side MUST be mirrored to the other: if §C2 gains, drops, or reworks
-> a check, this agent's checklist follows, and vice-versa. The two must never
-> drift. This is the same relationship `references/longform-quality-rules.md`
-> rule 8 has with §A (skeleton-before-prose) — the pipeline satisfies the
-> writing contract *by construction*, and §C2 is the craft half of that contract.
-
-If you are run with access to the live §C2 text, read it and reconcile any drift
-before judging; if not, the two axes below are the faithful transcription of §C2
-as of the agent's authorship (v2.4.0) and you judge against them.
+> **Mirror rule (only when you have §C2).** If — and only if — you are run with
+> access to the live §C2 text (the author's own runs), read it and reconcile any
+> drift before judging: §C2 is the upstream contract, this checklist its in-tree
+> transcription, and the two should not diverge. This mirrors the relationship
+> `references/longform-quality-rules.md` rule 8 has with §A (skeleton-before-prose).
+> **Absent §C2 (the default for any adopter), judge against the in-tree checklist
+> as the complete, authoritative source — its absence is not a gap.**
 
 ## The Two Axes
 
@@ -236,9 +236,11 @@ before the Step 6 persona sweep. Operator decides fold-in; this is [OPERATØR].
 7. **The operator gates, you recommend.** Your output is a report for KTG, not a
    pipeline stop. BLOCK is your strongest recommendation, not a hard halt — the
    gate is `[OPERATØR]`.
-8. **§C2 is the source of truth.** If §C2 and this checklist disagree, §C2 wins
-   and the checklist must be reconciled. Flag the drift; do not judge against a
-   stale checklist.
+8. **The in-tree checklist is the operative source of truth.** It ships and is
+   self-contained — judge against it. §C2 (the upstream contract) is available
+   only on the author's own runs; *if* you have it and it disagrees with this
+   checklist, flag the drift so the two can be reconciled. Absent §C2, its
+   absence is not a gap.
 
 ## Anti-Patterns
 
@@ -261,9 +263,11 @@ before the Step 6 persona sweep. Operator decides fold-in; this is [OPERATØR].
 ## References
 
 Read these for the contract and the pipeline position:
-- **Maskinrommet skrivekontrakt §C2** — the source of truth this checklist
-  mirrors (craft + architecture half of the writing contract; §A is the
+- **Maskinrommet skrivekontrakt §C2** — the author's upstream contract this
+  in-tree checklist transcribes (craft + architecture half; §A is the
   skeleton-before-prose half codified in `longform-quality-rules.md` rule 8).
+  **Does not ship** — available only on the author's own runs; the in-tree
+  checklist above is the self-contained source for everyone else.
 - `${CLAUDE_PLUGIN_ROOT}/references/longform-quality-rules.md` — the broad Step 4
   quality pass; this agent is the *finer* craft+architecture gate that runs after
   it (rule 1 ≈ A5 overload; rule 3 ≈ some prose nits — defer the AI-tell face to