fix(linkedin-studio): honest saves/dwell wording, no false tracking claim

Wave 2 / Step 7 of the remediation plan (research/02 D2/D4).

The tool parses the LinkedIn analytics CSV export, which has no saves/dwell — and
there is no self-serve API to pull them. Stop implying it tracks them:
- report.md: replace "Saves (10x weight) and expert comments (7-9x) are the
  highest-impact signals" with honest wording — saves rank highest in the
  engagement ORDER (cite references/algorithm-signals-reference.md, not a restated
  coefficient), but are visible only in native LinkedIn post analytics (count-only,
  ~Sept 2025+) with no self-serve API, so this tool does not auto-track them; dwell
  is internal to LinkedIn for organic posts.
- types.ts: document why PostMetrics intentionally omits saves/dwell (no ingest
  source) so a future contributor does not "add the missing fields".
- strategy.md: reconcile two saves references (signature-content criterion +
  authority scorecard) to say the count is read from native LinkedIn analytics, not
  captured by this tool.

No new metric field, no manual-entry feature (operator Q3).

Verify: report.md has no "Saves (10x"/"highest-impact signals" and does say "no
self-serve API"; tsc --noEmit clean; analytics suite 106/106; structural lint
0 failed (report.md cites the reference, so stat-consistency stays green).

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

plugins/linkedin-studio/scripts/analytics/src/models/types.ts

@@ -14,6 +14,11 @@ export interface PostMetrics {
   shares: number;
   clicks: number;
   engagementRate: number; // (reactions+comments+shares+clicks)/impressions * 100
+  // NOTE: `saves` and `dwell` are intentionally absent. They are NOT in the
+  // LinkedIn analytics CSV export this tool parses, and there is no self-serve API
+  // to pull them. Saves are visible (count-only) in the native post analytics UI
+  // (~Sept 2025 onward) — read them there; dwell is internal to LinkedIn for
+  // organic posts. Do not add these fields without a real ingest source.
 }
 
 export interface AnalyticsBatch {