docs: describe the OSE feature update and launchers

Update the feature list and explain first-run setup, branding and administrator configuration.

README.md

@@ -18,7 +18,9 @@ The server does not contain Nintendo NAS, DNS interception, SSLv3/TLS gateway co
 - Optional username/password accounts.
 - Guest posting and comments tied to the source IP when no account is logged in.
 - Text comments on the website and DSi, plus one-frame mini Flipnote comments from Flipnote Studio.
-- A minimal web admin page for IP bans and Flipnote deletion.
+- Paginated web and DSi browsing, search, channel management, creator controls and reversible content hiding.
+- Server branding and posting settings, a first-run setup helper and portable backups.
+- A web admin page for channels, server settings, Flipnote/comment moderation and IP bans.
 - Three anonymised sample Flipnotes copied from a production database so a fresh checkout has content to browse.
 - Newly generated geometric NTFT/NPF placeholder assets. The web client uses the RexiMemo logo with an Open Source Edition subtitle; other production artwork and all bundled font files are omitted.
 
@@ -34,12 +36,18 @@ Passwords are stored with a simple SHA-256 digest in this reference edition. Tha
 
 Use Python 3.10 or newer.
 
+**Recommended:** double-click **Start-OSE.cmd** on Windows, or run **`sh start-ose.sh`** on Linux/macOS. The first run creates a local Python environment, installs dependencies and asks for your server name, port and administrator login. Later runs reuse that setup. Stop the server with **Ctrl+C**.
+
+The setup helper disables the public `reximemo` / `alpine` login when you choose another administrator. It keeps the sample Flipnotes and existing accounts. See [GETTING_STARTED.md](GETTING_STARTED.md) for setup, updating, checks, backups and Linux service instructions.
+
+For an existing Python environment, the direct commands remain available:
+
 ```sh
 python3 -m pip install -r requirements.txt
 python3 server.py
 ```
 
-The default port is `8080`. Set `REXIMEMO_PORT` to use another port.
+The default port is `8080`. Setup saves your choices in `server-settings.json`; `REXIMEMO_PORT` overrides its port. Administrators can change the server name, tagline, welcome message, colour, logo and posting options on the website. Restart after changing the listen address or port.
 
 A detailed built-in documentation page can be enabled explicitly:
 
@@ -55,14 +63,14 @@ For Flipnote Studio on a DSi, OSE only provides the Hatena HTTP server/proxy por
 
 This split is deliberate: authentication/NAS, private keys and the production network-security implementation are not included in OSE, reducing the risk of exposing sensitive live-service security material in the public repository. Do not add production credentials or private authentication code to the checkout.
 
-The seeded administrator account is:
+If the setup helper has not been used, the legacy seed administrator account is:
 
 ```text
 username: reximemo
 password: alpine
 ```
 
-Change or remove that account before using the server anywhere outside a local test setup.
+Run `python3 manage.py setup` to select your own administrator and disable this public credential. Setup does not change OSE's simplified IP-based identity model.
 
 ## Web Flipnote playback