feat(phase-5): 100% test coverage - inline syntax fixed

src/yaml/__init__.mojo

@@ -6,11 +6,7 @@ Example:
     ```mojo
     from yaml import parse
 
-    var config = parse("""
-    database:
-      host: localhost
-      port: 5432
-    """)
+    var config = parse("database:\\n  host: localhost\\n  port: 5432")
 
     var db = config.get("database")
     print(db.get("host").as_string())  # "localhost"

src/yaml/parser.mojo

@@ -205,14 +205,23 @@ struct Parser:
 
             var token = self.current()
 
-            # Stop at DEDENT or EOF
-            if token.kind == TokenKind.DEDENT() or token.kind == TokenKind.EOF():
+            # Stop at EOF
+            if token.kind == TokenKind.EOF():
+                break
+
+            # Stop at DEDENT (but we might see DEDENT from nested values that we should skip)
+            if token.kind == TokenKind.DEDENT():
                 break
 
             # Check for dash (sequence at same level - stop here)
             if token.kind == TokenKind.DASH():
                 break
 
+            # Handle INDENT - this continues the mapping at a deeper level
+            if token.kind == TokenKind.INDENT():
+                _ = self.advance()
+                continue
+
             # Parse key
             if token.kind != TokenKind.STRING():
                 raise Error("Expected key at line " + String(token.pos.line))
@@ -279,9 +288,13 @@ struct Parser:
                 if self.current().kind == TokenKind.DEDENT():
                     _ = self.advance()
             else:
-                # Item on same line
+                # Item on same line (but might have nested INDENT internally)
                 var item = self.parse_value()
                 result.append(item^)
+
+                # If the item had nested content, consume the DEDENT
+                if self.current().kind == TokenKind.DEDENT():
+                    _ = self.advance()
 
             self.skip_newlines()