[feat](trx-rs): show server/client build info in HTTP footer

Add compile-time build dates for trx-server and trx-frontend-http, propagate server build metadata through rig state/snapshot, and render both versions + build dates in the HTTP footer.

Co-authored-by: OpenAI Codex <codex@openai.com>
Signed-off-by: Stanislaw Grams <stanislawgrams@gmail.com>

src/trx-server/Cargo.toml

@@ -6,6 +6,7 @@
 name = "trx-server"
 version = "0.1.0"
 edition = "2021"
+build = "build.rs"
 
 [dependencies]
 tokio = { workspace = true, features = ["full"] }