Add DocC comments for the numeric and string static methods

Author: andrewheard

FirebaseVertexAI/Sources/Schema.swift

@@ -102,6 +102,25 @@ public class Schema {
     self.requiredProperties = requiredProperties
   }
 
+  /// Returns a `Schema` representing a string value.
+  ///
+  /// This schema instructs the model to produce data of type ``DataType/string``, which is suitable
+  /// for decoding as a Swift `String` (or `String?`, if ``nullable`` is set to `true`).
+  ///
+  /// > Tip: If a specific set of string values should be generated by the model (for example,
+  /// > "north", "south", "east", or "west"), use ``enumeration(values:description:nullable:)``
+  /// > instead to constrain the generated values.
+  ///
+  /// - Parameters:
+  ///   - description: An optional description of what the string should contain or represent; may
+  ///     use Markdown format.
+  ///   - nullable: If `true`, instructs the model that it *may* generate `null` instead of a
+  ///     string; defaults to `false`, enforcing that a string value is generated.
+  ///   - format: An optional modifier describing the expected format of the string. Currently no
+  ///     formats are officially supported for strings but custom values may be specified using
+  ///     ``StringFormat/custom(_:)``, for example `.custom("email")` or `.custom("byte")`; these
+  ///     provide additional hints for how the model should respond but are not guaranteed to be
+  ///     adhered to.
   public static func string(description: String? = nil, nullable: Bool = false,
                             format: StringFormat? = nil) -> Schema {
     return self.init(
@@ -112,6 +131,27 @@ public class Schema {
     )
   }
 
+  /// Returns a `Schema` representing an enumeration of string values.
+  ///
+  /// This schema instructs the model to produce data of type ``DataType/string`` with the
+  /// ``format`` `"enum"`. This data is suitable for decoding as a Swift `String` (or `String?`,
+  /// if ``nullable`` is set to `true`), or an `enum` with strings as raw values.
+  ///
+  /// **Example:**
+  /// The values `["north", "south", "east", "west"]` for an enumation of directions.
+  /// ```
+  /// enum Direction: String, Decodable {
+  ///   case north, south, east, west
+  /// }
+  /// ```
+  ///
+  /// - Parameters:
+  ///   - values: The list of string values that may be generated by the model.
+  ///   - description: An optional description of what the `values` contain or represent; may use
+  ///     Markdown format.
+  ///   - nullable: If `true`, instructs the model that it *may* generate `null` instead of one of
+  ///     the strings specified in `values`; defaults to `false`, enforcing that one of the string
+  ///     values is generated.
   public static func enumeration(values: [String], description: String? = nil,
                                  nullable: Bool = false) -> Schema {
     return self.init(
@@ -123,6 +163,21 @@ public class Schema {
     )
   }
 
+  /// Returns a `Schema` representing a single-precision floating-point number.
+  ///
+  /// This schema instructs the model to produce data of type ``DataType/number`` with the
+  /// ``format`` `"float"`, which is suitable for decoding as a Swift `Float` (or `Float?`, if
+  /// ``nullable`` is set to `true`).
+  ///
+  /// > Important: This `Schema` provides a hint to the model that it should generate a
+  /// > single-precision floating-point number, a `float`, but only guarantees that the value will
+  /// > be a number.
+  ///
+  /// - Parameters:
+  ///   - description: An optional description of what the number should contain or represent; may
+  ///     use Markdown format.
+  ///   - nullable: If `true`, instructs the model that it may generate `null` instead of a number;
+  ///     defaults to `false`, enforcing that a number is generated.
   public static func float(description: String? = nil, nullable: Bool = false) -> Schema {
     return self.init(
       type: .number,
@@ -132,6 +187,21 @@ public class Schema {
     )
   }
 
+  /// Returns a `Schema` representing a double-precision floating-point number.
+  ///
+  /// This schema instructs the model to produce data of type ``DataType/number`` with the
+  /// ``format`` `"double"`, which is suitable for decoding as a Swift `Double` (or `Double?`, if
+  /// ``nullable`` is set to `true`).
+  ///
+  /// > Important: This `Schema` provides a hint to the model that it should generate a
+  /// > double-precision floating-point number, a `double`, but only guarantees that the value will
+  /// > be a number.
+  ///
+  /// - Parameters:
+  ///   - description: An optional description of what the number should contain or represent; may
+  ///     use Markdown format.
+  ///   - nullable: If `true`, instructs the model that it may return `null` instead of a number;
+  ///     defaults to `false`, enforcing that a number is returned.
   public static func double(description: String? = nil, nullable: Bool = false) -> Schema {
     return self.init(
       type: .number,
@@ -141,6 +211,26 @@ public class Schema {
     )
   }
 
+  /// Returns a `Schema` representing an integer value.
+  ///
+  /// This schema instructs the model to produce data of type ``DataType/integer``, which is
+  /// suitable for decoding as a Swift `Int` (or `Int?`, if ``nullable`` is set to `true`) or other
+  /// integer types (such as `Int32`) based on the expected size of values being generated.
+  ///
+  /// > Important: If a ``format`` of ``IntegerFormat/int32`` or ``IntegerFormat/int64`` is
+  /// > specified, this provides a hint to the model that it should generate 32-bit or 64-bit
+  /// > integers but this `Schema` only guarantees that the value will be an integer. Therefore, it
+  /// > is *possible* that decoding as an `Int32` could overflow even if a ``format`` of
+  /// > ``IntegerFormat/int32`` is specified.
+  ///
+  /// - Parameters:
+  ///   - description: An optional description of what the integer should contain or represent; may
+  ///     use Markdown format.
+  ///   - nullable: If `true`, instructs the model that it may return `null` instead of an integer;
+  ///     defaults to `false`, enforcing that an integer is returned.
+  ///   - format: An optional modifier describing the expected format of the integer. Currently the
+  ///     formats ``IntegerFormat/int32`` and ``IntegerFormat/int64`` are supported; custom values
+  ///     may be specified using ``IntegerFormat/custom(_:)`` but may be ignored by the model.
   public static func integer(description: String? = nil, nullable: Bool = false,
                              format: IntegerFormat? = nil) -> Schema {
     return self.init(