fix(analysis): guardrails against model repetition loops

Small vision models (qwen3-vl-4b) sometimes loop the OCR array, running
the response into the token ceiling (finish_reason: length) and failing to
parse. Layered guardrails:

- Prompts: explicit "transcribe each element once, never repeat/loop, at
  most N, STOP when done" in the OCR, grounding and combined prompts.
- Schema: hard maxItems on ocr_results/tagging_results/content_type and
  maxLength on text/scene — LM Studio's grammar enforces these, so a loop
  is grammar-bounded rather than relying on max_tokens.
- Sampling: a configurable frequency_penalty (ANALYSIS_FREQUENCY_PENALTY,
  default 0.3) sent with each request — the decode-time lever that actually
  breaks loops.
- Code: sanitize() collapses runaway consecutive duplicates (same
  normalized text + kind) so a loop that slips through still can't flood
  the row.

Tests: schema caps present, frequency_penalty included only when nonzero,
sanitize collapses consecutive repeats; config default.

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

frontend/package.json

@@ -1,6 +1,6 @@
 {
   "name": "mangalord-frontend",
-  "version": "0.79.0",
+  "version": "0.79.1",
   "private": true,
   "type": "module",
   "scripts": {