chore: move to public gitea instance and drop project-local gitea MCP

- Remove the project-local gitea MCP (opencode.json) and gitea-mcp-server
  from the dev shell — the gitea MCP is now installed globally and points
  at https://gitea.edley.me
- Update README/project.md links and the flake package homepage to the
  new public instance
- The GITEA_ACCESS_TOKEN for the old homeserver is removed from
  .secrets.env (gitignored); the global token from /run/secrets is used

flake.nix

@@ -71,7 +71,7 @@
 
           meta = with pkgs.lib; {
             description = "Stream a screen and audio to OBS Teleport receivers";
-            homepage = "http://homeserver:3050/pedley/TeleportFling";
+            homepage = "https://gitea.edley.me/petere/TeleportFling";
             license = licenses.gpl2;
             mainProgram = "teleportfling";
             platforms = platforms.linux;
@@ -96,7 +96,7 @@
 
           meta = with pkgs.lib; {
             description = "TeleportFling desktop GUI and system tray";
-            homepage = "http://homeserver:3050/pedley/TeleportFling";
+            homepage = "https://gitea.edley.me/petere/TeleportFling";
             license = licenses.gpl2;
             mainProgram = "teleportfling-gui";
             platforms = platforms.linux;
@@ -124,7 +124,6 @@
             gopls
             nixd
             nodejs
-            gitea-mcp-server
           ];
           buildInputs = with pkgs; [
             git