feat(campaign): plan export + execution-by-reuse (v5.7 Fase 2 Block 4c)

Completes Block 4 (4b backlog + 4c export/execution). Asymmetric: plan
export is new testable code; execution is pure reuse of the existing
per-repo implement/rollback (no new execution machinery), per the plan's
"reuse existing backup/rollback".

Plan export ("planer følger arbeidsstedet"):
- scanners/lib/campaign-export.mjs (pure, now injected, 8 tests):
  planExportPath(repo,sessionId) -> <repo>/docs/config-audit-plan-<sessionId>.md
  (sessionId-keyed so same-day re-audits never collide);
  buildPlanExportDocument({...,now}) -> provenance header + verbatim plan.
- scanners/campaign-export-cli.mjs (-cli, read-only by default, 10 tests):
  --repo resolves the repo's linked session, reads its action-plan.md,
  assembles the doc, emits {exportable,problems,targetPath,document}. Two
  gates -> exit 1 advisory: no-session-linked / no-action-plan. Writes the
  file ONLY under opt-in --write (byte-faithful copy; the LLM never re-types
  a 200-line plan). --sessions-dir override for hermetic tests; exit 0/1/3.

Command: commands/campaign.md gains an `export <path>` mode (Step 6:
preview -> approve -> --write), then routes the user to the existing
/config-audit implement (backup + verify) + rollback + set-status
implemented. Nothing auto-written (Verifiseringsplikt).

Byte-stable: lib + -cli + command-doc only -> scanner count stays 15,
agents 7, commands 21 (export is a mode, not a new command), SC-5 +
backcompat suite untouched. suite 1150->1168. Block 4a (migrateLedger)
still deferred to the first breaking schema change.

Docs: CLAUDE.md section + badge 1150->1168/65->67 files; README badge +
campaign row + Testing prose (fixed stale 1055/59 -> true 1168/67).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

CLAUDE.md

@@ -35,7 +35,7 @@ Analyzes and optimizes Claude Code configuration across three pillars:
 | `/config-audit plugin-health` | Audit plugin structure, frontmatter, cross-plugin coherence |
 | `/config-audit whats-active` | Read-only inventory of plugins, skills, MCP, hooks, CLAUDE.md active for a repo (with token estimates) |
 | `/config-audit knowledge-refresh` | Keep the best-practices register fresh — deterministic stale check (sources older than ~90d) + web candidate poll (CC changelog + Anthropic blog); **human-approved writes only** (Verifiseringsplikt). The "living" half of the knowledge base. Web/judgment-driven, **not byte-stable** |
-| `/config-audit campaign` | Machine-wide audit campaign — durable ledger ABOVE sessions: per-repo lifecycle (pending→audited→planned→implemented) + machine-wide roll-up by severity, resumable across sessions. Read-only report (campaign-cli) + **human-approved** writes via a deterministic write-CLI (init/add/set-status). THIN: tracks state, doesn't run audits/fixes. Judgment-driven, **not byte-stable** |
+| `/config-audit campaign` | Machine-wide audit campaign — durable ledger ABOVE sessions: per-repo lifecycle (pending→audited→planned→implemented) + machine-wide roll-up by severity + cross-repo prioritized backlog + plan **export** (drop a planned repo's plan into its own `docs/`), resumable across sessions. Read-only report (campaign-cli) + **human-approved** writes via deterministic write/export CLIs. THIN: tracks+routes state, reuses existing implement/rollback for execution. Judgment-driven, **not byte-stable** |
 | `/config-audit discover` | Run discovery phase only |
 | `/config-audit analyze` | Run analysis phase only |
 | `/config-audit interview` | Gather user preferences (opt-in) |
@@ -113,7 +113,7 @@ Default: auto-detects scope from git context. Override with `/config-audit full|
 node --test 'tests/**/*.test.mjs'
 ```
 
-1150 tests across 65 test files (21 lib + 34 scanner + 1 hook + 1 agent + 3 commands + 1 knowledge + 4 top-level). Test fixtures in `tests/fixtures/`. Top-level humanizer tests: `json-backcompat.test.mjs`, `raw-backcompat.test.mjs`, `scenario-read-test.test.mjs`, `snapshot-default-output.test.mjs`.
+1168 tests across 67 test files (22 lib + 35 scanner + 1 hook + 1 agent + 3 commands + 1 knowledge + 4 top-level). Test fixtures in `tests/fixtures/`. Top-level humanizer tests: `json-backcompat.test.mjs`, `raw-backcompat.test.mjs`, `scenario-read-test.test.mjs`, `snapshot-default-output.test.mjs`.
 
 ### active-config-reader — load-pattern model + rule/agent/output-style enumeration (v5.6 Foundation)
 
@@ -507,6 +507,32 @@ export to each repo's `docs/` + reuse of backup/rollback for execution. **Deferr
 breaking schema change:** `migrateLedger` (4a) — backlog needs no schema bump, so building
 migration now would be speculative (`schemaVersion` is already stamped for when it's needed).
 
+### campaign plan-export + execution-by-reuse (v5.7 Fase 2, Block 4c — the rest of Block 4)
+
+The second half of Block 4. **Asymmetric:** plan export is the new testable code; execution is
+*pure reuse* (no new machinery), per the plan's "reuse existing backup/rollback".
+
+- **Plan export** (`scanners/lib/campaign-export.mjs`, pure, 8 tests): `planExportPath(repoPath,
+  sessionId)` → `<repo>/docs/config-audit-plan-<sessionId>.md` (keyed on the timestamp-unique
+  sessionId, not the date, so same-day re-audits don't collide); `buildPlanExportDocument({...,now})`
+  → provenance header (repo/session/how-to-execute-and-undo) + the verbatim session plan. `now`
+  injected → deterministic. **CLI** `scanners/campaign-export-cli.mjs` (`-cli`, read-only by
+  default, 10 tests): `--repo <path>` resolves the repo's linked session, reads its
+  `action-plan.md`, assembles the doc, emits `{exportable, problems, targetPath, document, ...}`.
+  Two gates → exit 1 advisory: `no-session-linked` (repo has no `sessionId`), `no-action-plan`
+  (linked session has no plan yet). Writes the file **only** under opt-in `--write` — the CLI does
+  the byte-faithful copy so a 200-line plan is never re-typed/mutated by the LLM. `--sessions-dir`
+  override for hermetic tests; exit 0/1/3 mirror the sibling CLIs.
+- **Execution = reuse.** No campaign-side execution code. The exported `docs/` file is the repo's
+  durable record; `/config-audit implement` still reads the canonical plan from the session
+  (backup + apply + verify), `/config-audit rollback` undoes, then `set-status <path> implemented`
+  records it. The command (`commands/campaign.md`, new `export <path>` mode) previews → asks → on
+  approval invokes `--write` → routes the user to that existing machinery.
+- **Byte-stable.** lib + `-cli` + command-doc only → scanner count stays **15**, agents **7**,
+  commands **21** (export is a *mode*, not a new command), snapshot/backcompat suite untouched.
+  suite 1150→1168 (lib +8, export-cli +10). **Block 4a (`migrateLedger`) still deferred** to the
+  first breaking schema change (export needs no schema bump).
+
 ## Gotchas
 
 - Session directories accumulate — use `/config-audit cleanup` to manage