Add gzip-aware crash upload and OTA staging build/deploy tooling.

This restores the interrupted stash work on a dedicated feature branch, including backend decoding support, Dockerized build scripts, and staging channel artifacts for end-to-end OTA validation.

Co-authored-by: Cursor <cursoragent@cursor.com>

examples/crash_reporter/backend/README.md

@@ -109,6 +109,22 @@ curl -X POST http://127.0.0.1:8080/api/upload.php \
   -d @../sample_crash_java.json
 ```
 
+**Gzip ingest** (Android sends `Content-Encoding: gzip`; plain JSON still works):
+
+```bash
+./scripts/test_gzip_upload.sh
+# BASE=https://apps.f0xx.org/app/androidcast_project/crashes ./scripts/test_gzip_upload.sh
+```
+
+On the **BE nginx** upload `location`, enable gunzip so PHP receives plain JSON (see `nginx.vm.conf`):
+
+```nginx
+gunzip on;
+gunzip_types application/json;
+```
+
+PHP also decodes gzip if the header reaches FPM (`read_crash_upload_body()` in `bootstrap.php`). After deploy, sync `public/` + `src/` and reload nginx.
+
 ## Production (nginx + PHP-FPM)
 
 **Deploy topology (FE/BE, ports, sshfs):** [docs/INFRA.md](../../../docs/INFRA.md).  

examples/crash_reporter/backend/nginx.conf

@@ -17,11 +17,13 @@ server {
     }
 
     location ~ ^/app/androidcast_project/crashes/api/upload\.php$ {
+        gunzip on;
+        gunzip_types application/json;
         alias /var/www/androidcast_crashes/public/api/upload.php;
         include fastcgi_params;
         fastcgi_param SCRIPT_FILENAME /var/www/androidcast_crashes/public/api/upload.php;
         fastcgi_pass unix:/run/php-fpm/www.sock;
-        client_max_body_size 4m;
+        client_max_body_size 8m;
     }
 
     location ~ ^/app/androidcast_project/crashes/.+\.php$ {

examples/crash_reporter/backend/nginx.vm.conf

@@ -36,12 +36,15 @@ server {
     }
 
     location = /app/androidcast_project/crashes/api/upload.php {
+        # Decompress gzip uploads from Android before PHP (needs ngx_http_gunzip_module).
+        gunzip on;
+        gunzip_types application/json;
         include fastcgi_params;
         fastcgi_pass unix:/run/php-fpm.socket;
         fastcgi_param SCRIPT_FILENAME /var/www/localhost/htdocs/apps/app/androidcast_project/android_cast/examples/crash_reporter/backend/public/api/upload.php;
         fastcgi_param SCRIPT_NAME /app/androidcast_project/crashes/api/upload.php;
         fastcgi_param REQUEST_URI $request_uri;
-        client_max_body_size 4m;
+        client_max_body_size 8m;
     }
 
     location ^~ /app/androidcast_project/crashes/ {

examples/crash_reporter/backend/public/api/upload.php

@@ -13,10 +13,13 @@
 declare(strict_types=1);
 require_once __DIR__ . '/../../src/bootstrap.php';
 
-$raw = file_get_contents('php://input');
-if ($raw === false || $raw === '') {
+$raw = read_crash_upload_body();
+if ($raw === null) {
     json_out(['ok' => false, 'error' => 'empty body'], 400);
 }
+if ($raw === false) {
+    json_out(['ok' => false, 'error' => 'invalid gzip body'], 400);
+}
 $data = json_decode($raw, true);
 if (!is_array($data)) {
     json_out(['ok' => false, 'error' => 'invalid json'], 400);

examples/crash_reporter/backend/scripts/test_gzip_upload.sh

@@ -0,0 +1,33 @@
+#!/bin/sh
+# Smoke-test gzip crash upload (plain JSON still accepted).
+# Usage: BASE=http://127.0.0.1:8080/app/androidcast_project/crashes ./scripts/test_gzip_upload.sh
+set -eu
+
+ROOT="$(cd "$(dirname "$0")/.." && pwd)"
+SAMPLE="${ROOT}/../sample_crash_java.json"
+BASE="${BASE:-http://127.0.0.1:8080/app/androidcast_project/crashes}"
+URL="${BASE}/api/upload.php"
+RID="gzip-test-$(date +%s)"
+
+if [ ! -f "$SAMPLE" ]; then
+  echo "Missing $SAMPLE" >&2
+  exit 1
+fi
+
+BODY="$(mktemp)"
+jq --arg rid "$RID" '.report_id = $rid' "$SAMPLE" > "$BODY"
+GZIP="$(mktemp)"
+gzip -c -f "$BODY" > "$GZIP"
+
+echo "POST plain JSON..."
+curl -sS -o /dev/null -w "plain:%{http_code}\n" -X POST "$URL" \
+  -H 'Content-Type: application/json' \
+  --data-binary @"$BODY"
+
+echo "POST gzip (Content-Encoding: gzip)..."
+curl -sS -w "\n%{http_code}\n" -X POST "$URL" \
+  -H 'Content-Type: application/json' \
+  -H 'Content-Encoding: gzip' \
+  --data-binary @"$GZIP"
+
+rm -f "$BODY" "$GZIP"

examples/crash_reporter/backend/src/bootstrap.php

@@ -79,6 +79,25 @@ function json_out(array $data, int $code = 200): void {
     exit;
 }
 
+/**
+ * Raw POST body for crash ingest. Supports plain JSON or Content-Encoding: gzip
+ * (when nginx gunzip is off or the client talks to PHP directly).
+ *
+ * @return string|null decoded JSON text, null if empty, false if gzip decode failed
+ */
+function read_crash_upload_body(): string|false|null {
+    $raw = file_get_contents('php://input');
+    if ($raw === false || $raw === '') {
+        return null;
+    }
+    $encoding = $_SERVER['HTTP_CONTENT_ENCODING'] ?? '';
+    if ($encoding !== '' && stripos($encoding, 'gzip') !== false) {
+        $decoded = @gzdecode($raw);
+        return $decoded === false ? false : $decoded;
+    }
+    return $raw;
+}
+
 /** Short lines for expandable list preview (not full report detail). */
 function report_brief_lines(array $row, bool $grouped): array {
     if ($grouped) {