fix(docs): don't need that file

SUBDIRECTORY_BUG_FIX.md

@@ -1,89 +0,0 @@
-# Subdirectory Discovery Bug Fix
-
-## Issue Summary
-
-The ETag optimization feature was failing to discover subdirectories during first-time scans, causing it to report "No known subdirectories" and miss thousands of files.
-
-### Root Cause
-
-In `src/services/webdav_service.rs:933-936`, the `check_subdirectories_for_changes` function was returning empty results when no subdirectories were previously tracked in the database:
-
-```rust
-// BUGGY CODE (before fix)
-if subdirectories.is_empty() {
-    info!("📁 No known subdirectories for {}, no changes to process", parent_path);
-    return Ok(Vec::new()); // ❌ This was the bug!
-}
-```
-
-This logic assumed that if a directory's ETag was unchanged, we only needed to check previously-known subdirectories. However, this failed for directories that hadn't been fully scanned before.
-
-### The Fix
-
-Changed the function to fall back to a full recursive scan when no subdirectories are known:
-
-```rust
-// FIXED CODE (after fix)
-if subdirectories.is_empty() {
-    info!("📁 No known subdirectories for {}, performing initial scan to discover structure", parent_path);
-    return self.discover_files_in_folder_impl(parent_path).await; // ✅ Fixed!
-}
-```
-
-### Files Changed
-
-1. **`src/services/webdav_service.rs:933-936`** - Fixed the core logic
-2. **`tests/integration_webdav_first_time_scan_tests.rs`** - New integration tests
-3. **`tests/unit_webdav_subdirectory_edge_cases_tests.rs`** - New unit tests
-
-### Test Coverage Added
-
-#### Integration Tests (`integration_webdav_first_time_scan_tests.rs`)
-- `test_first_time_directory_scan_with_subdirectories()` - Tests the exact bug scenario
-- `test_subdirectory_tracking_after_full_scan()` - Verifies proper tracking after discovery
-- `test_direct_child_identification_edge_cases()` - Tests path logic with realistic paths
-- `test_file_count_accuracy_per_directory()` - Verifies correct file counting
-- `test_size_calculation_accuracy()` - Verifies size calculations
-
-#### Unit Tests (`unit_webdav_subdirectory_edge_cases_tests.rs`)
-- `test_comprehensive_directory_extraction()` - Tests directory structure extraction
-- `test_first_time_scan_scenario_logic()` - Tests the exact bug logic
-- `test_directory_etag_mapping_accuracy()` - Tests ETag handling
-- `test_direct_file_counting_precision()` - Tests file counting logic
-- `test_total_size_calculation_per_directory()` - Tests size calculations
-- `test_path_edge_cases_and_normalization()` - Tests path handling edge cases
-- `test_bug_scenario_file_count_verification()` - Specifically tests the 7046 files scenario
-
-### Expected Behavior Now
-
-**Before Fix:**
-```
-📁 No known subdirectories for /FullerDocuments/JonDocuments, no changes to process
-Found 0 files in folder /FullerDocuments/JonDocuments
-```
-
-**After Fix:**
-```
-📁 No known subdirectories for /FullerDocuments/JonDocuments, performing initial scan to discover structure
-[Performs full recursive scan]
-Found 7046 files in folder /FullerDocuments/JonDocuments
-```
-
-### Why This Fix is Safe
-
-1. **Performance**: Only affects first-time scans or completely empty directories
-2. **Correctness**: Ensures all files are discovered even when ETag optimization is enabled
-3. **Backward Compatibility**: Doesn't change behavior for directories with known subdirectories
-4. **Robustness**: Falls back to the tried-and-tested full scan method
-
-### Test Verification
-
-The fix has been verified with comprehensive test coverage that includes:
-- Real-world directory structures similar to the user's environment
-- Edge cases for path handling and file counting
-- Integration scenarios that test the full optimization workflow
-- Unit tests that isolate the specific logic that was failing
-
-### Summary
-
-This fix ensures that the ETag optimization feature works correctly for first-time directory scans while maintaining all the performance benefits for subsequent scans where subdirectories are already known.