Workouts 2.0: re-base persistence on iCloud Drive documents

Replace Core Data + NSPersistentCloudKitContainer + App-Group store +
WatchConnectivity dictionary sync with the QuickRabbit iCloud-documents
architecture:

- iCloud Drive JSON documents are the sole source of truth (one file per
  aggregate: Splits/<ULID>.json, Workouts/YYYY/MM/<ULID>.json), with a
  rebuildable SwiftData cache populated only by an NSMetadataQuery observer
  and a connect-time reconcile. Soft-delete tombstones; hard iCloud gate.
- Shared model layer (ULID, Codable *Documents + stateless mappers, @Model
  cache entities, SwiftData container) compiled into both targets.
- New iPhone<->Watch bridge over WatchConnectivity keyed by ULIDs; the phone
  is the sole writer of iCloud Drive, the watch round-trips documents.
- AppServices DI + iCloud-required root gate; Swift 6 strict concurrency.
- Starter splits generated on demand from the bundled YAML catalogs.
- Migrate to XcodeGen (project.yml), iOS 26 / watchOS 26; CloudDocuments
  entitlement (drop CloudKit/App Group/aps-environment).
- Duration stored as Int seconds (was a Date epoch hack); fix workout
  end-on-create, undismissable delete dialog, toolbar-hiding nav stacks,
  and the Settings placeholder.
- Add README/CHANGELOG/LICENSE, .gitignore, refreshed REQUIREMENTS, and the
  Scripts/ TestFlight pipeline (release.sh + ASC API scripts).

MARKETING_VERSION 2.0.

Scripts/update_build_number.sh

@@ -1,35 +0,0 @@
-#!/bin/sh
-
-## IMPORTANT ##
-# Add the following files to Input Files configuraiton of the build phase
-# $(TARGET_BUILD_DIR)/$(INFOPLIST_PATH)
-# $(DWARF_DSYM_FOLDER_PATH)/$(DWARF_DSYM_FILE_NAME)/Contents/Info.plist
-
-git=$(sh /etc/profile; which git)
-number_of_commits=$("$git" rev-list HEAD --count)
-git_release_version=$("$git" describe --tags --always --abbrev=0)
-
-target_plist="$TARGET_BUILD_DIR/$INFOPLIST_PATH"
-dsym_plist="$DWARF_DSYM_FOLDER_PATH/$DWARF_DSYM_FILE_NAME/Contents/Info.plist"
-
-git_commit=`"$git" rev-parse --short HEAD`
-bundle_version=`/usr/libexec/PlistBuddy -c "Print :CFBundleShortVersionString" "$target_plist"`
-build_date=`date +%F`
-
-build="v$bundle_version-$git_commit b$number_of_commits $build_date"
-
-#echo "version=$bundle_version-$git_commit build $number_of_commits"
-
-"$git" tag "$bundle_version"
-
-for plist in "$target_plist" "$dsym_plist"; do
-  if [ -f "$plist" ]; then
-    /usr/libexec/PlistBuddy -c "Set :CFBundleVersion $number_of_commits" "$plist"
-#    /usr/libexec/PlistBuddy -c "Set :CFBundleShortVersionString ${version}" "$plist"
-#    /usr/libexec/PlistBuddy -c "Set :CFBundleShortVersionString ${git_release_version#*v}" "$plist"
-
-    # Add build date for AppInfoKit
-    /usr/libexec/PlistBuddy -c "Set :BuildDate $build_date" "$plist" 2>/dev/null || \
-    /usr/libexec/PlistBuddy -c "Add :BuildDate string $build_date" "$plist"
-  fi
-done