Update signing configuration to use 88oakapps.feels identifiers

- Update App Group IDs from group.com.tt.feels to group.com.88oakapps.feels
- Update iCloud container IDs from iCloud.com.tt.feels to iCloud.com.88oakapps.feels
- Sync code constants with entitlements across all targets (iOS, Watch, Widget)
- Update documentation in CLAUDE.md and PROJECT_OVERVIEW.md

Co-Authored-By: Claude Opus 4.5 <noreply@anthropic.com>

FeelsWidgetExtensionDev.entitlements

@@ -6,7 +6,7 @@
 	<string>development</string>
 	<key>com.apple.developer.icloud-container-identifiers</key>
 	<array>
-		<string>iCloud.com.tt.feelsDebug</string>
+		<string>iCloud.com.88oakapps.feels.debug</string>
 	</array>
 	<key>com.apple.developer.icloud-services</key>
 	<array>
@@ -14,7 +14,7 @@
 	</array>
 	<key>com.apple.security.application-groups</key>
 	<array>
-		<string>group.com.tt.feelsDebug</string>
+		<string>group.com.88oakapps.feels.debug</string>
 	</array>
 </dict>
 </plist>