chore(cursor-proxy-debugger): enhance traffic capture for Fork Chat and update README

- Added support for capturing and decoding Fork Chat traffic, including `ForkBackgroundComposer`, `NotifyConversationClone`, and `UploadConversationBlobs`.
- Updated the README to reflect new features and usage instructions for Fork Chat traffic.
- Modified `.gitignore` to include `proto/extensions-cursor-app/`.
- Refactored `Taskfile.yml` to improve error messages related to Cursor extensions.
- Introduced new tests for decoding functionality in `cursor-proxy-debugger`.

proto/extract_extensions_proto.sh

@@ -2,22 +2,8 @@
 set -euo pipefail
 
 SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
-SNAPSHOT_DEFAULT="$SCRIPT_DIR/extensions-cursor-app/cursor-always-local"
 INSTALLED_CURSOR_DEFAULT="/Applications/Cursor.app/Contents/Resources/app/extensions/cursor-always-local/dist/main.js"
-LATEST_EXT_DIR="$(
-  find "$SCRIPT_DIR" -maxdepth 1 -type d -name 'extensions-*' 2>/dev/null \
-    | sort -V \
-    | tail -n 1
-)"
-if [[ -f "$SNAPSHOT_DEFAULT/dist/main.js" ]]; then
-  INPUT_DEFAULT="$SNAPSHOT_DEFAULT"
-elif [[ -f "$INSTALLED_CURSOR_DEFAULT" ]]; then
-  INPUT_DEFAULT="$INSTALLED_CURSOR_DEFAULT"
-elif [[ -n "$LATEST_EXT_DIR" ]]; then
-  INPUT_DEFAULT="$LATEST_EXT_DIR"
-else
-  INPUT_DEFAULT="$SCRIPT_DIR/extensions-2.6.19"
-fi
+INPUT_DEFAULT="$INSTALLED_CURSOR_DEFAULT"
 OUTPUT_DEFAULT="$SCRIPT_DIR/from_extensions"
 
 INPUT_PATH="${1:-$INPUT_DEFAULT}"
@@ -57,7 +43,8 @@ fi
 
 if [[ ! -f "$INPUT_PATH" ]]; then
   echo "Input JS not found: $INPUT_PATH" >&2
-  echo "Usage: $0 [input-js-file-or-extensions-dir] [output-dir]" >&2
+  echo "Install/update Cursor, or pass an explicit input bundle:" >&2
+  echo "  $0 /path/to/cursor-always-local/dist/main.js [output-dir]" >&2
   exit 1
 fi