fix: resolve all 301 error handling anti-patterns across codebase

Systematic cleanup of every error handling anti-pattern detected by the
automated scanner. 289 issues fixed via code changes, 12 approved with
specific technical justifications.

Changes across 90 files:
- GENERIC_CATCH (141): Added instanceof Error type discrimination
- LARGE_TRY_BLOCK (82): Extracted helper methods to narrow try scope to ≤10 lines
- NO_LOGGING_IN_CATCH (65): Added logger/console calls for error visibility
- CATCH_AND_CONTINUE_CRITICAL_PATH (10): Added throw/return or approved overrides
- ERROR_STRING_MATCHING (2): Approved with rationale (no typed error classes)
- ERROR_MESSAGE_GUESSING (1): Replaced chained .includes() with documented pattern array
- PROMISE_CATCH_NO_LOGGING (1): Added logging to .catch() handler

Also fixes a detector bug where nested try/catch inside a catch block
corrupted brace-depth tracking, causing false positives.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

src/shared/worker-utils.ts

@@ -148,7 +148,7 @@ function getPluginVersion(): string {
     const packageJson = JSON.parse(readFileSync(packageJsonPath, 'utf-8'));
     return packageJson.version;
   } catch (error: unknown) {
-    const code = (error as NodeJS.ErrnoException).code;
+    const code = error instanceof Error ? (error as NodeJS.ErrnoException).code : undefined;
     if (code === 'ENOENT' || code === 'EBUSY') {
       logger.debug('SYSTEM', 'Could not read plugin version (shutdown race)', { code });
       return 'unknown';
@@ -176,30 +176,39 @@ async function getWorkerVersion(): Promise<string> {
  * Skips comparison when either version is 'unknown' (fix #1042 — avoids restart loops).
  */
 async function checkWorkerVersion(): Promise<void> {
+  let pluginVersion: string;
   try {
-    const pluginVersion = getPluginVersion();
-
-    // Skip version check if plugin version couldn't be read (shutdown race)
-    if (pluginVersion === 'unknown') return;
-
-    const workerVersion = await getWorkerVersion();
-
-    // Skip version check if worker version is 'unknown' (avoids restart loops)
-    if (workerVersion === 'unknown') return;
-
-    if (pluginVersion !== workerVersion) {
-      // Just log debug info - auto-restart handles the mismatch in worker-service.ts
-      logger.debug('SYSTEM', 'Version check', {
-        pluginVersion,
-        workerVersion,
-        note: 'Mismatch will be auto-restarted by worker-service start command'
-      });
-    }
-  } catch (error) {
-    // Version check is informational — don't fail the hook
-    logger.debug('SYSTEM', 'Version check failed', {
+    pluginVersion = getPluginVersion();
+  } catch (error: unknown) {
+    logger.debug('SYSTEM', 'Version check failed reading plugin version', {
       error: error instanceof Error ? error.message : String(error)
     });
+    return;
+  }
+
+  // Skip version check if plugin version couldn't be read (shutdown race)
+  if (pluginVersion === 'unknown') return;
+
+  let workerVersion: string;
+  try {
+    workerVersion = await getWorkerVersion();
+  } catch (error: unknown) {
+    logger.debug('SYSTEM', 'Version check failed reading worker version', {
+      error: error instanceof Error ? error.message : String(error)
+    });
+    return;
+  }
+
+  // Skip version check if worker version is 'unknown' (avoids restart loops)
+  if (workerVersion === 'unknown') return;
+
+  if (pluginVersion !== workerVersion) {
+    // Just log debug info - auto-restart handles the mismatch in worker-service.ts
+    logger.debug('SYSTEM', 'Version check', {
+      pluginVersion,
+      workerVersion,
+      note: 'Mismatch will be auto-restarted by worker-service start command'
+    });
   }
 }