feat: infer status url and check updates

README.md

@@ -9,25 +9,23 @@ Run once from a public Git repo with `uvx`:
 
 ```bash
 uvx --from git+https://gitea.shujk.top/shujakuin/shusub2.git shusub2 \
-  --api-url https://example.com/api/tui/accounts
+  --api-url https://codex.server2.shujk.top/1232131231313123/api/tui/accounts
 ```
 
 Install as a user command:
 
 ```bash
 uv tool install git+https://gitea.shujk.top/shujakuin/shusub2.git
-shusub2 --api-url https://example.com/api/tui/accounts
+shusub2 --api-url https://codex.server2.shujk.top/1232131231313123/api/tui/accounts
 ```
 
-Configure default API and optional status URLs for `shusub2`:
+Configure the default public API URL for `shusub2`:
 
 ```bash
 mkdir -p ~/.config/shusub2
 chmod 700 ~/.config/shusub2
-printf '%s\n' 'https://example.com/api/tui/accounts' > ~/.config/shusub2/api-url
-printf '%s\n' 'https://example.com/api/status' > ~/.config/shusub2/status-url
+printf '%s\n' 'https://codex.server2.shujk.top/1232131231313123/api/tui/accounts' > ~/.config/shusub2/api-url
 chmod 600 ~/.config/shusub2/api-url
-chmod 600 ~/.config/shusub2/status-url
 shusub2
 ```
 
@@ -38,6 +36,9 @@ Environment variables override the config file:
 - `SHUSUB2_API_URL_FILE`
 - `SHUSUB2_STATUS_URL`
 - `SHUSUB2_STATUS_URL_FILE`
+- `SHUSUB2_VERSION_CHECK_URL`
+- `SHUSUB2_VERSION_CHECK_TIMEOUT`
+- `SHUSUB2_NO_VERSION_CHECK`
 
 ## Local Development
 
@@ -64,6 +65,12 @@ The TUI reads `/api/tui/accounts` and can optionally read `sub2api-status`
 `/api/status` for channel monitor health. It does not need SSH, database
 access, API keys, OAuth credentials, or plaintext env files.
 
+When `--status-url` is omitted, `shusub2` infers a sibling `/api/status` URL
+from account URLs ending in `/api/tui/accounts`, so the public Codex endpoint
+automatically enables monitor availability. On startup it also checks the
+public Gitea repo for a newer package version and prints a short upgrade hint
+when one is available.
+
 Columns are ordered for scanning inside zellij:
 
 ```text