v0.4.3: Lock contention overhaul, StoragePool, mobile bottom nav, text scaling

Eliminate all conn_mgr lock holds during network I/O across 14 actor commands
and bi-stream handlers. PostFetch, TcpPunch, PullFromPeer, FetchEngagement,
ResolveAddress, AnchorProbe use brief locks for data gathering only. WormLookup,
ContentSearch, WormQuery use connection snapshots for lock-free cascade fan-out.
RelayIntroduce extracts forwarding data under brief lock, does I/O outside.
BlobRequest, PostFetchRequest, ManifestRefresh use Arc clones instead of conn_mgr
lock. ConnectionActor hoists shared Arcs (storage, blob_store, endpoint) for
lock-free access. ResolveAddress adds 5s per-query timeout (was unbounded).

Initial exchange failure now aborts mesh upgrade (was silently continuing with
broken connection). connect_to_peer/connect_to_anchor use consistent 15s timeout.
Rebalance connects outside the lock via pending_connects pattern.

StoragePool: 8 concurrent SQLite connections in WAL mode replace single
Mutex<Storage>. Reads run fully parallel; writes serialize at SQLite level only.
PRAGMA busy_timeout=5000 for graceful write contention.

Mobile bottom nav bar (<=768px) with icon tabs. Text sizes: XS/S/M/L/XL
(75%/100%/125%/150%/200%), default M. localStorage persistence for instant
restore. Toast repositioned above mobile nav.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

crates/core/src/protocol.rs

@@ -287,7 +287,7 @@ pub struct RefuseRedirectPayload {
 }
 
 /// Worm lookup query (bi-stream) — searches for nodes, posts, or blobs
-#[derive(Debug, Serialize, Deserialize)]
+#[derive(Debug, Clone, Serialize, Deserialize)]
 pub struct WormQueryPayload {
     pub worm_id: WormId,
     pub target: NodeId,