feat: miller column browser, offline cache, search, breadcrumbs

- Dynamic miller column sizing with flexbox layout
- Root column (160px), middle slices (48px), active column (flex)
- Auto-scroll browser to rightmost column on navigation
- Offline indicator UI and IndexedDB cache integration
- /api/documents endpoint for client-side document caching
- Breadcrumb navigation in document content area
- FTS5 search with SQLite virtual table
- Client-side Mermaid and KaTeX rendering via CDN
- Deep sample content (advanced-topics/raft-deep-dive)
- Border removal (only search button keeps radius)
- Full viewport layout with proper borders between sidebar/content

content/advanced-topics/distributed-systems/consensus-algorithms/raft-deep-dive/configuration.md

@@ -0,0 +1,37 @@
+# Raft Configuration
+
+Configuration options for running a Raft cluster in production.
+
+## Cluster Size
+
+For fault tolerance with `f` failures, you need `2f + 1` nodes:
+
+- 3 nodes: tolerates 1 failure
+- 5 nodes: tolerates 2 failures  
+- 7 nodes: tolerates 3 failures
+
+## Election Timeout
+
+The election timeout should be:
+
+- At least 10x the network round-trip time (RTT)
+- Typically 150-300ms in a single datacenter
+- 500ms-2s across regions
+
+## Heartbeat Interval
+
+Set to roughly 1/3 to 1/10 of the election timeout:
+
+```
+heartbeat_interval = election_timeout / 3
+```
+
+## Log Compaction
+
+Configure snapshot creation when the log grows too large:
+
+| Threshold | Description |
+|-----------|-------------|
+| 10,000 entries | Minimum for frequent writes |
+| 100MB | Size-based threshold |
+| Daily | Time-based for low-write workloads |