refactor: fix warnings in dash spv (#110)

* fix: remove dead code and fix warnings (89% reduction: 76→8 warnings)

This commit addresses dead code warnings and other compiler warnings across
the dash-spv crate, reducing total warnings from 76 to 8 (89% reduction).

## Dead Code Removed:
- client/mod.rs: 12 unused methods (handle_inventory, process_new_headers, etc.)
- client/filter_sync.rs: 1 unused method (find_height_for_block_hash)
- client/message_handler.rs: 1 unused field (filter_processor) + constructor updates
- network/mod.rs: 1 unused field (message_receiver) + constructor updates
- network/multi_peer.rs: 2 unused methods (select_peer, send_to_peer)
- sync/chainlock_validation.rs: 1 unused method (find_chain_lock_quorum)
- sync/filters.rs: 4 unused constants + 3 unused fields + constructor fixes

## Other Fixes:
- Removed 2 unused imports (FilterNotificationSender, BLSPublicKey)
- Fixed private interface: made ChainLockStats public
- Updated method calls and constructors to remove unused parameters

## Files Modified:
- dash-spv/src/client/filter_sync.rs: removed unused method
- dash-spv/src/client/message_handler.rs: removed unused field and import
- dash-spv/src/client/mod.rs: removed 12 unused methods
- dash-spv/src/network/mod.rs: removed unused field
- dash-spv/src/network/multi_peer.rs: removed 2 unused methods
- dash-spv/src/sync/chainlock_validation.rs: removed unused method, fixed visibility
- dash-spv/src/sync/filters.rs: removed unused constants and fields

🤖 Generated with [Claude Code](https://claude.ai/code)

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

* fix: complete dead code cleanup and resolve import warnings (92% reduction: 76→6 warnings)

This commit completes the systematic cleanup of compiler warnings in dash-spv:

### Fixed Issues:
- **Unused imports**: Removed ForkDetectionResult, ReorgManager, ValidationManager
- **Dead code cleanup**: Removed entire SyncStorageAdapter struct and implementation
- **Unused struct fields**: Added #[allow(dead_code)] annotations for RecoveryEvent fields
- **Unused enum variants**: Added #[allow(dead_code)] for ValidationCacheKey::ChainLock
- **Orphaned code**: Cleaned up remaining code fragments from previous method removals

### Files Modified:
- client/mod.rs: Removed duplicate find_height_for_block_hash method
- headers_with_reorg.rs: Major cleanup - removed unused imports, SyncStorageAdapter, tests
- recovery.rs: Added dead_code annotations for unused but intentional fields
- validation.rs: Added dead_code annotation for ChainLock cache key

### Warning Reduction:
- **Before**: 76 warnings (52 deprecated + 24 dead code)
- **After**: 6 warnings (unused variables in stub methods)
- **Improvement**: 92% reduction in compiler warnings

### Remaining Warnings:
- 3 unused parameters in stub methods (intentional - methods kept for interface compatibility)
- 3 unused methods in client and headers modules (future functionality)

The project now builds cleanly with significantly reduced noise from compiler warnings,
making genuine issues more visible to developers.

🤖 Generated with [Claude Code](https://claude.ai/code)

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

* refactor: more warnings resolved

* refactor: simplify error handling and improve code readability

* chore: run cargo fmt

---------

Co-authored-by: Claude <noreply@anthropic.com>

Author: PastaPastaPasta

dash-spv/src/client/filter_sync.rs

@@ -1,20 +1,18 @@
 //! Filter synchronization and management for the Dash SPV client.
 
-#![allow(deprecated)]
-
 use std::sync::Arc;
 use tokio::sync::RwLock;
 
 use crate::error::{Result, SpvError};
 use crate::network::NetworkManager;
 use crate::storage::StorageManager;
-use crate::sync::SyncManager;
+use crate::sync::sequential::SequentialSyncManager;
 use crate::types::SpvStats;
 use crate::types::{FilterMatch, WatchItem};
 
 /// Filter synchronization manager for coordinating filter downloads and checking.
 pub struct FilterSyncCoordinator<'a, S: StorageManager, N: NetworkManager> {
-    sync_manager: &'a mut SyncManager<S, N>,
+    sync_manager: &'a mut SequentialSyncManager<S, N>,
     storage: &'a mut S,
     network: &'a mut N,
     watch_items: &'a Arc<RwLock<std::collections::HashSet<WatchItem>>>,
@@ -27,7 +25,7 @@ impl<'a, S: StorageManager + Send + Sync + 'static, N: NetworkManager + Send + S
 {
     /// Create a new filter sync coordinator.
     pub fn new(
-        sync_manager: &'a mut SyncManager<S, N>,
+        sync_manager: &'a mut SequentialSyncManager<S, N>,
         storage: &'a mut S,
         network: &'a mut N,
         watch_items: &'a Arc<RwLock<std::collections::HashSet<WatchItem>>>,
@@ -165,10 +163,4 @@ impl<'a, S: StorageManager + Send + Sync + 'static, N: NetworkManager + Send + S
         let watch_items = self.watch_items.read().await;
         watch_items.iter().cloned().collect()
     }
-
-    /// Helper method to find height for a block hash.
-    async fn find_height_for_block_hash(&self, block_hash: dashcore::BlockHash) -> Option<u32> {
-        // Use the efficient reverse index
-        self.storage.get_header_height_by_hash(&block_hash).await.ok().flatten()
-    }
 }

dash-spv/src/client/message_handler.rs

@@ -8,7 +8,6 @@ use crate::error::{Result, SpvError};
 use crate::mempool_filter::MempoolFilter;
 use crate::network::NetworkManager;
 use crate::storage::StorageManager;
-use crate::sync::filters::FilterNotificationSender;
 use crate::sync::sequential::SequentialSyncManager;
 use crate::types::{MempoolState, SpvEvent, SpvStats};
 
@@ -19,7 +18,6 @@ pub struct MessageHandler<'a, S: StorageManager, N: NetworkManager> {
     network: &'a mut N,
     config: &'a ClientConfig,
     stats: &'a Arc<RwLock<SpvStats>>,
-    filter_processor: &'a Option<FilterNotificationSender>,
     block_processor_tx: &'a tokio::sync::mpsc::UnboundedSender<crate::client::BlockProcessingTask>,
     mempool_filter: &'a Option<Arc<MempoolFilter>>,
     mempool_state: &'a Arc<RwLock<MempoolState>>,
@@ -36,7 +34,6 @@ impl<'a, S: StorageManager + Send + Sync + 'static, N: NetworkManager + Send + S
         network: &'a mut N,
         config: &'a ClientConfig,
         stats: &'a Arc<RwLock<SpvStats>>,
-        filter_processor: &'a Option<FilterNotificationSender>,
         block_processor_tx: &'a tokio::sync::mpsc::UnboundedSender<
             crate::client::BlockProcessingTask,
         >,
@@ -50,7 +47,6 @@ impl<'a, S: StorageManager + Send + Sync + 'static, N: NetworkManager + Send + S
             network,
             config,
             stats,
-            filter_processor,
             block_processor_tx,
             mempool_filter,
             mempool_state,