feat(docs): add production readiness runbook and enhanced TODO scan

Add comprehensive production readiness checklist and improve TODO scanning.

Changes:
- Production Readiness Runbook (docs/progress/PRODUCTION-READINESS-RUNBOOK.md)
  - Complete mechanical execution checklist for TypeScript, Android, iOS
  - File anchors and search commands for verification
  - Cross-platform behavior consistency checks
  - Logging and observability requirements
  - Release packaging sanity checks
  - Troubleshooting guide
  - Quick reference for expected file anchors
- Enhanced TODO Scan Script (scripts/todo-scan.js)
  - Split reporting: core code vs docs/test-apps
  - Core code count (should be 0)
  - Docs/test-apps count (expected to be large)
  - Enhanced JSON output with summary statistics
  - Improved console output with visual indicators
  - Clear separation of production code vs planning artifacts

Implementation Details:
- Core code detection: ios/Plugin/, android/src/main/, src/, packages/, lib/
- Docs/test-apps detection: docs/, test-apps/, tests/, *Tests/
- JSON output includes summary with coreCount, docsTestCount, otherCount
- Markdown output includes summary section with split counts
- Console output shows visual indicators (✅/⚠️) for quick assessment

Benefits:
- Clear visibility into production code TODOs (should be 0)
- Acceptable TODOs in docs/test-apps are clearly separated
- Production readiness checklist provides deterministic verification
- File anchors enable quick verification of implementation completeness

Verification:
- TODO scan runs successfully
- JSON output includes summary statistics
- Markdown output includes split summary
- Console output shows visual indicators

scripts/todo-scan.js

@@ -94,6 +94,29 @@ function bucketForPath(rel) {
   return "Other";
 }
 
+function isCoreCode(rel) {
+  // Core code directories (production code)
+  return (
+    rel.startsWith("ios/Plugin/") ||
+    rel.startsWith("android/src/main/") ||
+    rel.startsWith("src/") ||
+    rel.startsWith("packages/") ||
+    rel.startsWith("lib/") ||
+    (rel.startsWith("scripts/") && !rel.includes("test"))
+  );
+}
+
+function isDocsOrTestApp(rel) {
+  // Documentation and test harness directories
+  return (
+    rel.startsWith("docs/") ||
+    rel.startsWith("test-apps/") ||
+    rel.startsWith("ios/Tests/") ||
+    rel.startsWith("android/src/test/") ||
+    rel.startsWith("tests/")
+  );
+}
+
 function main() {
   const results = [];
   for (const d of TARGET_DIRS) {
@@ -113,7 +136,27 @@ function main() {
     a.line - b.line
   );
 
-  fs.writeFileSync(path.join(ROOT, "docs/todo-scan.json"), JSON.stringify(results, null, 2), "utf8");
+  // Split core vs docs/test-apps
+  const coreResults = results.filter(r => isCoreCode(r.file));
+  const docsTestResults = results.filter(r => isDocsOrTestApp(r.file));
+  const otherResults = results.filter(r => !isCoreCode(r.file) && !isDocsOrTestApp(r.file));
+
+  // Enhanced JSON output with split counts
+  const jsonOutput = {
+    summary: {
+      total: results.length,
+      coreCount: coreResults.length,
+      docsTestCount: docsTestResults.length,
+      otherCount: otherResults.length,
+      generatedAt: new Date().toISOString()
+    },
+    core: coreResults,
+    docsTest: docsTestResults,
+    other: otherResults,
+    all: results
+  };
+
+  fs.writeFileSync(path.join(ROOT, "docs/todo-scan.json"), JSON.stringify(jsonOutput, null, 2), "utf8");
 
   // markdown
   const byBucket = new Map();
@@ -125,7 +168,13 @@ function main() {
   let md = "";
   md += `# TODO Classification (auto-generated)\n\n`;
   md += `Generated by \`scripts/todo-scan.js\`\n\n`;
-  md += `Total markers: **${results.length}**\n\n`;
+  md += `## Summary\n\n`;
+  md += `- **Total markers:** ${results.length}\n`;
+  md += `- **Core code (production):** ${coreResults.length} ⚠️\n`;
+  md += `- **Docs/test-apps:** ${docsTestResults.length} ✅ (expected)\n`;
+  md += `- **Other:** ${otherResults.length}\n\n`;
+  md += `> **Note:** Core code TODOs should be near zero. Docs/test-app TODOs are expected and acceptable.\n\n`;
+  md += `---\n\n`;
 
   for (const [bucket, items] of byBucket.entries()) {
     md += `## ${bucket} (${items.length})\n\n`;
@@ -146,7 +195,14 @@ function main() {
 
   fs.writeFileSync(path.join(ROOT, "docs/TODO-CLASSIFICATION.md"), md, "utf8");
 
-  console.log(`todo-scan complete: ${results.length} markers`);
+  // Console output with split summary
+  console.log(`\n📊 TODO Scan Complete`);
+  console.log(`━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━`);
+  console.log(`Total markers:     ${results.length}`);
+  console.log(`Core code:         ${coreResults.length} ${coreResults.length === 0 ? '✅' : '⚠️  (should be 0)'}`);
+  console.log(`Docs/test-apps:    ${docsTestResults.length} ✅ (expected)`);
+  console.log(`Other:             ${otherResults.length}`);
+  console.log(`━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━\n`);
 }
 
 main();