docs(readme): use underscore emphasis for consistency

Author: farhan-syah

README.md

@@ -53,7 +53,7 @@ It already powers **ma8e**, an in-development memory-and-knowledge layer for cod
 ## Why NodeDB
 
 - **Memory that runs where the agent runs.** The same engines embed on device and in the browser (NodeDB-Lite, WASM), work offline, and sync conflict-free to the server (CRDT). A cloud vector store can't embed next to your agent; a markdown file isn't queryable or access-guarded.
-- **All of an agent's memory in one query.** Vector search, graph traversal, full-text ranking, document storage, timeseries, and key-value share one storage core, one identity space, and one planner — so a query flows from semantic search into graph traversal filtered by full-text, in one process with no network hops. Multi-model is *how* NodeDB does this; the point is the capability, not the label.
+- **All of an agent's memory in one query.** Vector search, graph traversal, full-text ranking, document storage, timeseries, and key-value share one storage core, one identity space, and one planner — so a query flows from semantic search into graph traversal filtered by full-text, in one process with no network hops. Multi-model is _how_ NodeDB does this; the point is the capability, not the label.
 - **PostgreSQL wire protocol.** Connect with `psql` or any PostgreSQL client library. Standard SQL with engine-specific extensions where SQL can't express the operation.
 - **One engine instead of a polyglot stack.** When you outgrow the edge, the same engine folds a server-side sprawl of separate systems into a single deployment — fewer services to run, no cross-system sync pipelines, no schema drift.
 - **Serious about performance.** Thread-per-Core data plane with io_uring, SIMD-accelerated distance functions, zero-copy MessagePack transport, per-column compression (ALP, FastLanes, FSST, Gorilla). See benchmarks below.