perf: Phase 1 critical performance fixes + production macOS build

Performance:
- Move JSON parsing to background isolate via Isolate.run() (eliminates 2-4s UI freeze)
- Cache filteredEntries with key-based invalidation (eliminates O(n) recomputation)
- Debounce search queries at 300ms (prevents cascade rebuilds on keystroke)
- Flatten timeline from 2-level turn×response Column to single virtualized ListView.builder
- Add RepaintBoundary per timeline item (isolates repaints during scroll)
- Use context.select for granular rebuilds instead of top-level context.watch
- Lazy ExpandableCard: child not built until first expand (replaces AnimatedCrossFade)
- Use IndexedStack in AppShell (preserves screen state across tab switches)

Fixes:
- Collect parse errors instead of silently swallowing them
- Show parse error count in timeline filter bar
- Fix overflow in tokens screen pie chart legend

Build:
- Configure Developer ID signing with hardened runtime for production distribution
- Enable secure timestamps for notarization
- Update app name to Claude Session Viewer
- Signed, notarized, stapled DMG distribution

macos/Runner.xcodeproj/project.pbxproj

@@ -671,7 +671,7 @@
 				CLANG_WARN_OBJC_ROOT_CLASS = YES_ERROR;
 				CLANG_WARN_RANGE_LOOP_ANALYSIS = YES;
 				CLANG_WARN_SUSPICIOUS_MOVE = YES;
-				CODE_SIGN_IDENTITY = "-";
+				CODE_SIGN_IDENTITY = "Developer ID Application";
 				COPY_PHASE_STRIP = NO;
 				DEAD_CODE_STRIPPING = YES;
 				DEBUG_INFORMATION_FORMAT = "dwarf-with-dsym";
@@ -720,7 +720,11 @@
 				ASSETCATALOG_COMPILER_APPICON_NAME = AppIcon;
 				CLANG_ENABLE_MODULES = YES;
 				CODE_SIGN_ENTITLEMENTS = Runner/Release.entitlements;
-				CODE_SIGN_STYLE = Automatic;
+				CODE_SIGN_IDENTITY = "Developer ID Application";
+				CODE_SIGN_STYLE = Manual;
+				"DEVELOPMENT_TEAM[sdk=macosx*]" = LD76P8L42W;
+				ENABLE_HARDENED_RUNTIME = YES;
+				OTHER_CODE_SIGN_FLAGS = "--timestamp --options runtime";
 				COMBINE_HIDPI_IMAGES = YES;
 				INFOPLIST_FILE = Runner/Info.plist;
 				LD_RUNPATH_SEARCH_PATHS = (

macos/Runner/Configs/AppInfo.xcconfig

@@ -5,10 +5,10 @@
 // 'flutter create' template.
 
 // The application's name. By default this is also the title of the Flutter window.
-PRODUCT_NAME = Claude Session Analysis
+PRODUCT_NAME = Claude Session Viewer
 
 // The application's bundle identifier
-PRODUCT_BUNDLE_IDENTIFIER = com.svrnty.claudeSessionAnalysis
+PRODUCT_BUNDLE_IDENTIFIER = com.svrnty.claude-session-viewer
 
 // The copyright displayed in application information
 PRODUCT_COPYRIGHT = Copyright © 2026 Svrnty. All rights reserved.