feat(egg): write the recommended PopupNotifications banner (runicnpc 9e, D327, D328)

The install writes PopupNotifications.json into oxide/config or
carbon/configs as a banner across the top of the screen, by the installer's
rule: only where the file is missing or every setting is still the plugin's
own default (the Version aside). Anything else is kept whole. The plugin's
Version is written or kept, because PopupNotifications resets a config
without one. A failed write is said in the console and does not fail the
install: it is a look, not the bridge.

Tested in ghcr.io/ptero-eggs/installers:debian: missing, the rig's defaults,
defaults from a later release (version kept), four kinds of change, not
JSON, an existing banner, and an unmakeable directory. egg/build.sh builds.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01E14m6SuuY6i1vASFeGDBeY

egg/install.sh

@@ -88,6 +88,69 @@ if [ $WORLD_SEED == "0" ]; then
 fi
 
 ## ── The Runic Gateway bridge ─────────────────────────────────────────────────
+# PopupNotifications' recommended look (docs/runicnpc/PLAN.md D327): a banner
+# across the top of the screen. PopupNotifications is optional and the operator
+# installs it (D141), so its config is theirs: the banner goes in only where the
+# file is missing or is still exactly the plugin's own defaults, every setting
+# equal and the Version aside (D328). Anything else is kept whole. The Version
+# is written too: PopupNotifications resets a config without one to defaults.
+rg_popup() { # <the framework's config directory>
+    local file="$1/PopupNotifications.json"
+    local banner='{
+      "Notification duration (in seconds)": 8,
+      "Maximum notifications shown at any time": 6,
+      "UI Positioning": {
+        "Position of the left side of notification (0.0 - 1.0)": 0.15,
+        "Position of the bottom of noticiation (0.0 - 1.0)": 0.87,
+        "Width (0.0 - 1.0)": 0.7,
+        "Height (0.0 - 1.0)": 0.07,
+        "Space between notification (0.0 - 1.0)": 0.005
+      },
+      "UI Options": {
+        "Show close button": false,
+        "Panel color (hex)": "#2b2b2b",
+        "Panel transparency (0.0 - 1.0)": 0.8,
+        "Close button color (hex)": "#d85540",
+        "Close button transparency (0.0 - 1.0)": 0.5,
+        "Font": "robotocondensed-bold.ttf",
+        "Font size": 18
+      },
+      "Version": { "Major": 0, "Minor": 2, "Patch": 1 }
+    }'
+    # PopupNotifications 0.2.1's GetBaseConfig(): a small grey box at the right.
+    local defaults='{
+      "Notification duration (in seconds)": 8,
+      "Maximum notifications shown at any time": 6,
+      "UI Positioning": {
+        "Position of the left side of notification (0.0 - 1.0)": 0.8,
+        "Position of the bottom of noticiation (0.0 - 1.0)": 0.78,
+        "Width (0.0 - 1.0)": 0.19,
+        "Height (0.0 - 1.0)": 0.1,
+        "Space between notification (0.0 - 1.0)": 0.01
+      },
+      "UI Options": {
+        "Show close button": true,
+        "Panel color (hex)": "#2b2b2b",
+        "Panel transparency (0.0 - 1.0)": 0.5,
+        "Close button color (hex)": "#d85540",
+        "Close button transparency (0.0 - 1.0)": 0.5,
+        "Font": "droidsansmono.ttf",
+        "Font size": 12
+      }
+    }'
+    if [ ! -e "${file}" ]; then
+        mkdir -p "$1" || return 1
+        jq -n "${banner}" > "${file}" || return 1
+        echo "Runic Gateway: wrote the recommended PopupNotifications banner to ${file}"
+    elif jq -e --argjson d "${defaults}" 'type == "object" and del(.Version) == $d' "${file}" >/dev/null 2>&1; then
+        jq --argjson b "${banner}" '$b + { Version: (.Version // $b.Version) }' "${file}" > "${file}.rg" \
+            && mv "${file}.rg" "${file}" || { rm -f "${file}.rg"; return 1; }
+        echo "Runic Gateway: ${file} was PopupNotifications' defaults; wrote the recommended banner"
+    else
+        echo "Runic Gateway: kept ${file} (not PopupNotifications' defaults)"
+    fi
+}
+
 # After the wipe, so REMOVE_FILES can never delete the plugin this just placed.
 rg_install() {
     set -euo pipefail
@@ -95,10 +158,10 @@ rg_install() {
     # just the variables an egg declares, and this one is not declared.
     local api="${RUNICGATEWAY_BUNDLE_API:-https://gitea.whitlocktech.com/api/v1/repos/RunicGateway/installer/contents/v2/rust}"
     local work=/tmp/runicgateway
-    local plugins
+    local plugins config
     case "${FRAMEWORK:-vanilla}" in
-        oxide)  plugins=/mnt/server/oxide/plugins ;;
+        oxide)  plugins=/mnt/server/oxide/plugins;  config=/mnt/server/oxide/config ;;
-        carbon) plugins=/mnt/server/carbon/plugins ;;
+        carbon) plugins=/mnt/server/carbon/plugins; config=/mnt/server/carbon/configs ;;
         *)
             # Not a failure (§34.4): failing would leave the operator without a game
             # server over a bridge they may not want yet. The startup skips the
@@ -188,6 +251,10 @@ rg_install() {
     for file in $(jq -r '.files | keys[]' "${manifest}"); do
         install -m 644 "${work}/runicgateway-rust-plugin/${file}" "${plugins}/${file}"
     done
+    # A look, not the bridge: if it cannot be written, say so and finish the install.
+    if ! rg_popup "${config}"; then
+        echo "Runic Gateway: could not write the PopupNotifications banner to ${config}; the bridge is installed regardless"
+    fi
     # What is installed, readable from the panel's file manager.
     jq --arg framework "${FRAMEWORK}" --arg installed "$(date -u +%Y-%m-%dT%H:%M:%SZ)" \
        '{ bundle, protocol, framework: $framework, installed: $installed,