Add WASM parser and Vue dissector UI.

Ship a working HexPigeon: typed binary parsing in Rust/WASM, a three-pane frontend, and unit tests covering the field types.

Co-authored-by: Cursor <cursoragent@cursor.com>

parser-wasm/src/schema.rs

@@ -0,0 +1,110 @@
+use serde::{Deserialize, Serialize};
+
+/// A full schema describing a binary frame layout.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct Schema {
+    /// Human-readable name for this schema.
+    pub name: Option<String>,
+    /// Endianness applied globally unless overridden per field.
+    #[serde(default = "default_endian")]
+    pub endian: Endian,
+    /// Ordered list of fields to parse.
+    pub fields: Vec<FieldDef>,
+}
+
+fn default_endian() -> Endian {
+    Endian::Big
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq)]
+#[serde(rename_all = "lowercase")]
+pub enum Endian {
+    Big,
+    Little,
+}
+
+/// A single field definition.
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct FieldDef {
+    /// Display name.
+    pub name: String,
+    /// Field type.
+    #[serde(rename = "type")]
+    pub kind: FieldKind,
+    /// Override global endianness for this field.
+    pub endian: Option<Endian>,
+    /// Description / comment shown in the tree.
+    pub description: Option<String>,
+    /// For bitflags: the flag definitions.
+    pub flags: Option<Vec<FlagDef>>,
+    /// For `bytes` type: number of bytes (required).
+    /// For `string_lp8` / `string_lp16`: omit (length is read from data).
+    /// For other types: derived from type width.
+    pub length: Option<usize>,
+    /// For `crc16` / `crc32`: byte range to checksum [start, end) relative to frame start.
+    pub checksum_range: Option<[usize; 2]>,
+    /// For `repeated`: how many repetitions (constant or from a previously parsed field name).
+    pub count: Option<CountSpec>,
+    /// For `repeated`: the inner fields to repeat.
+    pub fields: Option<Vec<FieldDef>>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq)]
+#[serde(rename_all = "snake_case")]
+pub enum FieldKind {
+    /// 1 byte unsigned.
+    Uint8,
+    /// 2 bytes unsigned.
+    Uint16,
+    /// 4 bytes unsigned.
+    Uint32,
+    /// 8 bytes unsigned.
+    Uint64,
+    /// 1 byte signed.
+    Int8,
+    /// 2 bytes signed.
+    Int16,
+    /// 4 bytes signed.
+    Int32,
+    /// 4 bytes float.
+    Float32,
+    /// 8 bytes float.
+    Float64,
+    /// 1-byte bitfield with named flags.
+    Bitflags8,
+    /// 2-byte bitfield with named flags.
+    Bitflags16,
+    /// Raw bytes of `length`.
+    Bytes,
+    /// Null-terminated string of `length` bytes.
+    StringFixed,
+    /// Pascal-style: 1-byte length prefix, then UTF-8 bytes.
+    StringLp8,
+    /// Pascal-style: 2-byte length prefix (respects endian), then UTF-8 bytes.
+    StringLp16,
+    /// CRC-16/CCITT checksum (2 bytes).
+    Crc16,
+    /// CRC-32 checksum (4 bytes).
+    Crc32,
+    /// Repeat inner `fields` `count` times.
+    Repeated,
+    /// Skip / padding bytes.
+    Padding,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+pub struct FlagDef {
+    /// Bit index (0 = LSB).
+    pub bit: u8,
+    pub name: String,
+    pub description: Option<String>,
+}
+
+#[derive(Debug, Clone, Serialize, Deserialize)]
+#[serde(untagged)]
+pub enum CountSpec {
+    /// Literal count.
+    Fixed(usize),
+    /// Name of a previously parsed uint field holding the count.
+    Field(String),
+}