[keichi]

Problem

sizeOf() returned wrong results for several fixed-size parsers:

new Parser().bit4("a").bit4("b").sizeOf();          // NaN (expected 1)
new Parser().seek("x").uint8("a").sizeOf();         // "0x1" (string concatenation)
new Parser().nest("n", { type: "A1" }).sizeOf();    // TypeError (alias type)
new Parser().array("a", { type: "A1", length: 2 }).sizeOf(); // NaN (alias type)
new Parser().saveOffset("o").uint8("a").sizeOf();   // NaN (expected 1)

Fix

• Bit fields: consecutive bit fields are summed and converted to bytes with the same grouping as generateBit (groups up to 32 bits, reads of 8/16/24/32 bits).
• seek: only counted when length is a number, otherwise NaN.
• nest / array: alias string types are resolved via the alias registry.
• pointer and saveOffset contribute 0 bytes.

Tests

Added regression tests in test/composite_parser.ts; the bit field test checks sizeOf() against the actual parse offset (saveOffset) for several bit layouts.