Implement user soft-delete and improve search ranking

Adds soft-delete support for local users, including backend, API, and UI changes to allow admins to delete local users while preserving their requests. Updates user queries to exclude deleted users and allows username reuse for deleted accounts. Refines search and ranking logic for torrents: uses title-only queries for broader results, increases max results to 100, applies a minimum score threshold (30/100), and logs detailed ranking breakdowns. Updates the ranking algorithm to prioritize title/author match, adjusts scoring weights, and improves BookDate compatibility with Audiobookshelf by disabling rating-based features when unsupported. Enhances file copy operations for large files, improves metadata tagging, and updates documentation to reflect new search and ranking strategies.

documentation/phase3/ranking-algorithm.md

@@ -1,29 +1,38 @@
 # Intelligent Ranking Algorithm
 
-**Status:** ❌ Not Implemented
+**Status:** ✅ Implemented
 
 Evaluates and scores torrents to automatically select best audiobook download.
 
 ## Scoring Criteria (100 points max)
 
-**1. Format Quality (40 pts max)**
-- M4B with chapters: 40
-- M4B without chapters: 35
-- M4A: 25
-- MP3: 15
-- Other: 5
+**1. Title/Author Match (50 pts max) - MOST IMPORTANT**
+- Title matching: 0-35 pts
+  - Exact substring match → 35 pts
+  - No exact match → fuzzy similarity (partial credit)
+- Author presence: 0-15 pts
+  - Splits authors on delimiters (comma, &, "and", " - ")
+  - Filters out roles ("translator", "narrator")
+  - Proportional credit for partial matches
+- Order-independent, no structure assumptions
+- Ensures correct book is selected over wrong book with better format
 
-**2. Seeder Count (25 pts max)**
-- Formula: `Math.min(25, Math.log10(seeders + 1) * 10)`
-- 1 seeder: 0pts, 10 seeders: 10pts, 100 seeders: 20pts, 1000+: 25pts
+**2. Format Quality (25 pts max)**
+- M4B with chapters: 25
+- M4B without chapters: 22
+- M4A: 16
+- MP3: 10
+- Other: 3
 
-**3. Size Reasonableness (20 pts max)**
+**3. Seeder Count (15 pts max)**
+- Formula: `Math.min(15, Math.log10(seeders + 1) * 6)`
+- 1 seeder: 0pts, 10 seeders: 6pts, 100 seeders: 12pts, 1000+: 15pts
+
+**4. Size Reasonableness (10 pts max)**
 - Expected: 1-2 MB/min (64-128 kbps)
-- Deviation from expected → penalty
-
-**4. Title Match Quality (15 pts max)**
-- Fuzzy match: title + author (Levenshtein distance)
-- Narrator bonus
+- Perfect match: 10 pts
+- Deviation → penalty
+- Unknown duration: 5 pts (neutral)
 
 ## Interface