quality: enforce typhon source LOC hygiene in CI

Jenkinsfile

@@ -122,6 +122,7 @@ spec:
 
             node <<'NODE'
 const fs = require('fs');
+const path = require('path');
 
 const junitPath = 'build/junit-typhon.xml';
 const coveragePath = 'coverage/coverage-summary.json';
@@ -143,6 +144,44 @@ const skipped = Number((junit.match(/skipped="([0-9]+)"/) || [])[1] || 0);
 
 const cov = JSON.parse(fs.readFileSync(coveragePath, 'utf8'));
 const total = cov.total || {};
+const sourceRoots = ['src', 'tests', 'scripts'];
+const sourceExts = new Set(['.ts', '.js', '.cjs', '.mjs', '.sh']);
+const maxSourceLines = 500;
+
+function collectOverLimitFiles(rootDir) {
+  const offenders = [];
+  const stack = [rootDir];
+  while (stack.length > 0) {
+    const current = stack.pop();
+    if (!fs.existsSync(current)) {
+      continue;
+    }
+    for (const entry of fs.readdirSync(current, { withFileTypes: true })) {
+      const fullPath = path.join(current, entry.name);
+      if (entry.isDirectory()) {
+        stack.push(fullPath);
+        continue;
+      }
+      if (!sourceExts.has(path.extname(entry.name))) {
+        continue;
+      }
+      const lines = fs.readFileSync(fullPath, 'utf8').split(/\\r?\\n/).length;
+      if (lines > maxSourceLines) {
+        offenders.push({ file: fullPath, lines });
+      }
+    }
+  }
+  return offenders;
+}
+
+const overLimitFiles = sourceRoots.flatMap((root) => collectOverLimitFiles(root));
+if (overLimitFiles.length > 0) {
+  console.error('source files exceed 500 LOC:');
+  for (const item of overLimitFiles) {
+    console.error(`- ${item.file}: ${item.lines}`);
+  }
+  process.exit(1);
+}
 
 const report = {
   suite: 'typhon',
@@ -158,6 +197,9 @@ const report = {
     statements: 85,
     functions: 85,
     branches: 75
+  },
+  hygiene: {
+    sourceLinesOver500: overLimitFiles.length
   }
 };
 
@@ -187,6 +229,7 @@ if (!fs.existsSync(qualityPath)) {
 
 const quality = JSON.parse(fs.readFileSync(qualityPath, 'utf8'));
 const status = quality.tests.failures > 0 || quality.tests.errors > 0 ? 'failed' : 'ok';
+const sourceLinesOver500 = Number(quality.hygiene?.sourceLinesOver500 ?? 0);
 
 function fetchCounter(targetStatus) {
   try {
@@ -219,6 +262,10 @@ const payload = [
   `typhon_quality_gate_coverage_percent{suite="${suite}",scope="statements"} ${quality.coverage.statements}`,
   `typhon_quality_gate_coverage_percent{suite="${suite}",scope="functions"} ${quality.coverage.functions}`,
   `typhon_quality_gate_coverage_percent{suite="${suite}",scope="branches"} ${quality.coverage.branches}`,
+  '# TYPE platform_quality_gate_workspace_line_coverage_percent gauge',
+  `platform_quality_gate_workspace_line_coverage_percent{suite="${suite}"} ${quality.coverage.lines}`,
+  '# TYPE platform_quality_gate_source_lines_over_500_total gauge',
+  `platform_quality_gate_source_lines_over_500_total{suite="${suite}"} ${sourceLinesOver500}`,
   ''
 ].join('\\n');