feat: optionally gzip large save uploads with fallback (#5259)

* feat: optionally gzip large save uploads with fallback

* fix: replace Safari-prone save compression with fflate fallback

* refactor: align save upload compression with review feedback

* refactor: use compressRequest wrapper for save uploads

* Refactor request compression settings

* Fix default value

* Avoid null in bytes parsing result

* fix: switch request compression to fflate gzip

* fix: add request compression maxBytes cap and clarify timeout semantics

* Refresh package-lock.json

* Unify payload limit setting names

* Expose compression termination function

* Add compression to group chat saves

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Co-authored-by: Roland4396 <Roland4396@users.noreply.github.com>
Co-authored-by: Cohee <18619528+Cohee1207@users.noreply.github.com>

default/config.yaml

@@ -202,6 +202,16 @@ performance:
   memoryCacheCapacity: '100mb'
   # Enables disk caching for character cards. Improves performances with large card libraries.
   useDiskCache: true
+  # Configures gzip compression for client requests with large payloads (e.g. settings or chat saves).
+  requestCompression:
+    # Enable request compression.
+    enabled: false
+    # Minimum payload size to trigger compression. Set to 0 to compress all requests regardless of size.
+    minPayloadSize: '256kb'
+    # Hard upper payload size limit for compression. Set to 0 to allow compression of any size.
+    maxPayloadSize: '8mb'
+    # Timeout for request compression in milliseconds.
+    timeout: 4000
 
 # CACHE BUSTER CONFIGURATION
 # IMPORTANT: Requires localhost or a domain with HTTPS, otherwise will not work!