chore(v0.8.1): version bump + CHANGELOG + ARCHITECTURE.md for reaper

Bump plugin header and PRAUTOBLOGGER_VERSION 0.8.0 → 0.8.1. Patch
bump — the reaper is internal infrastructure; no user-visible UX
change.

CHANGELOG:
- Fixed: orphan `llm_research` rows now reaped daily.
- Added: WP-CLI `wp prautoblogger reap-research`; `_prautoblogger_run_id`
  post_meta is now written by Publisher on every post.

ARCHITECTURE.md:
- Decision #13 (Run-ID based log linking) cross-refs the new post_meta.
- New Decision #19 documents the reaper's scan/amortize/delete policy,
  the 1-hour grace window, the 7-day stale cutoff, and the one-shot
  activator back-populate migration.

DB schema unchanged — no PRAUTOBLOGGER_DB_VERSION bump.

Final commit of the v0.8.1 bundle.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

prautoblogger.php

@@ -8,7 +8,7 @@ declare(strict_types=1);
  * Plugin Name:       PRAutoBlogger
  * Plugin URI:        https://peptiderepo.com/prautoblogger
  * Description:       Monitors social media for trending topics, generates SEO-friendly blog posts using AI, and publishes them on a daily schedule with full cost tracking and self-improvement metrics.
- * Version:           0.8.0
+ * Version:           0.8.1
  * Requires at least: 6.0
  * Requires PHP:      7.4
  * Author:            PeptideRepo
@@ -35,7 +35,7 @@ if ( ! defined( 'ABSPATH' ) ) {
 | and limits without magic strings.
 */
 
-define( 'PRAUTOBLOGGER_VERSION', '0.8.0' );
+define( 'PRAUTOBLOGGER_VERSION', '0.8.1' );
 define( 'PRAUTOBLOGGER_DB_VERSION', '1.1.0' );
 define( 'PRAUTOBLOGGER_PLUGIN_FILE', __FILE__ );
 define( 'PRAUTOBLOGGER_PLUGIN_DIR', plugin_dir_path( __FILE__ ) );