docs: update version pins from 5.0 to 5.1

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

Author: userFRM

README.md

@@ -44,7 +44,7 @@ No-JVM ThetaData Terminal - native Rust SDK for direct market data access.
 
 ```toml
 [dependencies]
-thetadatadx = "5.0"
+thetadatadx = "5.1"
 tokio = { version = "1", features = ["rt-multi-thread", "macros"] }
 ```
 

docs-site/docs/getting-started.md

@@ -11,7 +11,7 @@ description: Install ThetaDataDx, configure credentials, and run your first quer
 ```toml [Rust]
 # Add to your Cargo.toml
 [dependencies]
-thetadatadx = "5.0"
+thetadatadx = "5.1"
 tokio = { version = "1", features = ["rt-multi-thread", "macros"] }
 ```
 ```bash [Python]

docs-site/docs/getting-started/installation.md

@@ -11,7 +11,7 @@ description: Install ThetaDataDx for Rust, Python, Go, or C++.
 ```toml [Rust]
 # Add to your Cargo.toml
 [dependencies]
-thetadatadx = "5.0"
+thetadatadx = "5.1"
 tokio = { version = "1", features = ["rt-multi-thread", "macros"] }
 ```
 ```bash [Python]