Fix broken flight axis override tests

The test_flight_axis_override.js file had multiple bugs preventing tests
from running correctly:

**Fix #1: Missing Decompiler import**
- Added `import { Decompiler } from '../decompiler.js';`
- Changed `transpiler.decompile()` to proper `new Decompiler()` usage
- Error was: "transpiler.decompile is not a function"

**Fix #2: Invalid property name in Test 4**
- Fixed `flight.armed` → `flight.isArmed`
- Error was: "Unknown property 'armed' in 'flight.armed'"
- The correct property is `isArmed` per the flight API

**Fix #3: Error message handling**
- Fixed `result.errors` → `result.error || result.errors`
- Fixed `decompiled.errors` → `decompiled.error || decompiled.errors`
- Handles both singular and plural error field names

**Test Results:**
Before: 3 decompile errors, 1 compilation failure
After: All 4 tests pass ✅

- Test 1: Roll angle override ✅
- Test 2: Pitch rate override ✅
- Test 3: Yaw angle override ✅
- Test 4: Multiple axis overrides ✅

Author: sensei-hacker

js/transpiler/transpiler/tests/test_flight_axis_override.js

@@ -5,6 +5,7 @@
  */
 
 import { Transpiler } from '../index.js';
+import { Decompiler } from '../decompiler.js';
 
 function testFlightAxisOverride() {
   console.log('Testing Flight Axis Override...\n');
@@ -45,7 +46,7 @@ if (flight.heading < 180) {
       code: `
 const { flight, override } = inav;
 
-if (flight.armed) {
+if (flight.isArmed) {
   override.flightAxis.roll.angle = 30;
   override.flightAxis.pitch.angle = -15;
   override.flightAxis.yaw.rate = 50;
@@ -77,16 +78,17 @@ if (flight.armed) {
         });
 
         // Test decompilation
-        const decompiled = transpiler.decompile(logicConditions);
+        const decompiler = new Decompiler();
+        const decompiled = decompiler.decompile(logicConditions);
         if (decompiled.success) {
           console.log('✓ Decompilation successful');
           console.log('Decompiled code:');
           console.log(decompiled.code);
         } else {
-          console.log('✗ Decompilation failed:', decompiled.errors);
+          console.log('✗ Decompilation failed:', decompiled.error || decompiled.errors);
         }
       } else {
-        console.log('✗ Compilation failed:', result.errors);
+        console.log('✗ Compilation failed:', result.error || result.errors);
       }
     } catch (error) {
       console.log('✗ Error:', error.message);