[fix](trx-server): include legacy home config path and coords in print-config

Fix server config discovery to include ~/.trx-server.toml and update
example/print-config output to explicitly include general latitude and
longitude fields.

Also update config docs and add a test for the legacy search path.

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

CONFIGURATION.md

@@ -8,8 +8,9 @@ This document lists all currently supported configuration options for `trx-serve
 Configuration lookup order:
 1. `--config <FILE>`
 2. `./trx-server.toml`
-3. `~/.config/trx-rs/server.toml`
-4. `/etc/trx-rs/server.toml`
+3. `~/.trx-server.toml`
+4. `~/.config/trx-rs/server.toml`
+5. `/etc/trx-rs/server.toml`
 
 ### `trx-client`
 Configuration lookup order: