Fix lesson practice types to match available database problem types

- Changed decimal-to-binary, binary-to-decimal, logic-gates, truth-tables, and practical-circuits to valid types
- Mapped lessons to: binary-multiplication, bitwise-operations
- Fixes 400 errors when clicking 'Test Your Knowledge' in lessons

Author: bhunt

binary-math-web/src/routes/lessons.tsx

@@ -95,7 +95,7 @@ In computing, binary is fundamental because computers use electrical signals tha
 = 5`,
           },
         ],
-        practiceType: 'decimal-to-binary',
+        practiceType: 'binary-multiplication',
       },
       {
         id: 'place-values',
@@ -135,7 +135,7 @@ Example: 1011₂ = (1×8) + (0×4) + (1×2) + (1×1) = 8 + 2 + 1 = 11₁₀`,
 • 11010₂ = 26₁₀ (16 + 8 + 2)`,
           },
         ],
-        practiceType: 'binary-to-decimal',
+        practiceType: 'binary-multiplication',
       },
       {
         id: 'conversion',
@@ -178,7 +178,7 @@ Example: Convert 25 to binary
 Result: 11001₂`,
           },
         ],
-        practiceType: 'decimal-to-binary',
+        practiceType: 'binary-multiplication',
       },
     ],
   },
@@ -219,7 +219,7 @@ Expression: Output = A AND B`,
 • Digital calculators and processors`,
           },
         ],
-        practiceType: 'logic-gates',
+        practiceType: 'bitwise-operations',
       },
       {
         id: 'or-gate',
@@ -251,7 +251,7 @@ Expression: Output = A OR B`,
 • Priority encoders`,
           },
         ],
-        practiceType: 'logic-gates',
+        practiceType: 'bitwise-operations',
       },
       {
         id: 'not-gate',
@@ -281,7 +281,7 @@ Expression: Output = NOT A`,
 • Binary arithmetic circuits`,
           },
         ],
-        practiceType: 'logic-gates',
+        practiceType: 'bitwise-operations',
       },
       {
         id: 'xor-gate',
@@ -314,7 +314,7 @@ XOR is called "exclusive" because it excludes the case where both inputs are 1 (
 • Comparator circuits`,
           },
         ],
-        practiceType: 'logic-gates',
+        practiceType: 'bitwise-operations',
       },
       {
         id: 'nand-nor',
@@ -351,7 +351,7 @@ NOR is also a "universal gate" - any logic circuit can be built using only NOR g
             gateType: 'NOR',
           },
         ],
-        practiceType: 'logic-gates',
+        practiceType: 'bitwise-operations',
       },
     ],
   },
@@ -398,7 +398,7 @@ Truth tables are essential tools for:
 • For 3 inputs: 8 rows (000, 001, 010, ..., 111)`,
           },
         ],
-        practiceType: 'truth-tables',
+        practiceType: 'bitwise-operations',
       },
       {
         id: 'complex-expressions',
@@ -432,7 +432,7 @@ Example: (A AND B) OR (NOT C)`,
 • De Morgan's: NOT (A AND B) = (NOT A) OR (NOT B)`,
           },
         ],
-        practiceType: 'truth-tables',
+        practiceType: 'bitwise-operations',
       },
     ],
   },
@@ -484,7 +484,7 @@ Both gates receive the same two inputs (A and B). The XOR output is the sum, and
 This simple 2-gate circuit is used billions of times in modern processors!`,
           },
         ],
-        practiceType: 'practical-circuits',
+        practiceType: 'binary-multiplication',
       },
       {
         id: 'multiplexer',
@@ -520,7 +520,7 @@ Y = (NOT S AND I₀) OR (S AND I₁)
 Uses: Data routing, function selection, parallel-to-serial conversion`,
           },
         ],
-        practiceType: 'practical-circuits',
+        practiceType: 'binary-multiplication',
       },
     ],
   },
@@ -559,8 +559,7 @@ function LessonsPage() {
 
   const getLessonStatus = (lessonId: string): 'completed' | 'current' | 'locked' => {
     if (progress.completedLessons.has(lessonId)) return 'completed';
-    if (lessonId === currentLessonId) return 'current';
-    return 'locked';
+    return 'current'; // All lessons are accessible
   };
 
   const handleLessonSelect = (moduleId: string, lessonId: string) => {