chore(linkedin-studio): release v0.5.1 — SB-S1 ingest + gold signal

Bump version declarations 0.5.0 → 0.5.1 (plugin.json SSOT + README badge +
CLAUDE.md header + CHANGELOG [0.5.1] entry) for SB-S1. Flip the architecture
SB-S1 row to landed (+ top status). Additive minor: no command/agent/ref/skill
count change; voice-trainer's learning behaviour changes (published-only).
Gate 93/0/0. Polyrepo release (tag v0.5.1 + catalog ref bump) pending push window
+ operator confirm (public open/ remote).

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01RigJBiRFNtFZKCz21qNbQ4

.claude-plugin/plugin.json

@@ -1,6 +1,6 @@
 {
   "name": "linkedin-studio",
-  "version": "0.5.0",
+  "version": "0.5.1",
   "description": "LinkedIn Studio — full-spectrum LinkedIn content engine: feed posts, carousels, video scripts, and long-form newsletter editions, with the 2026 relevance-ranking model baked in. v4.0.0 is an audit-remediation release (Voyage Phase 0–3): every user-facing claim is made honest or removed, all 11 previously-orphaned agents are wired (→ 19 agents), a `/linkedin:firsthour` post-publish command is added (→ 27 commands), the algorithm-signal claims are reconciled to one sourced statement (no unpublishable model name or date), short-form de-AI and video quality gates are added, and the structure lint is rebuilt to guard the real layout plus version/count/stat consistency. Breaking: the newly-wired agents register only on reinstall/reload, and this consolidates the v3.0.0 identity break (slug, agent namespace `linkedin-studio:<agent>`, state-file path `~/.claude/linkedin-studio.local.md`). v3.1.0 added the cold adversarial review package (`/linkedin:headless-review` + Step 6.5 + `/linkedin:pivot` + per-artifact personas); the `/linkedin:*` commands are unchanged. v4.1.0 adds a journey layer: two guided front-doors (`/linkedin:create`, `/linkedin:measure`) plus a router re-tiered into five journeys (Start · Create · Engage · Measure · Grow), with the 27 existing commands kept as the execution tier (→ 29 commands; additive, reload registers the two new commands).",
   "author": {
     "name": "Kjell Tore Guttormsen"