@gba-kit/debug-info: add support for DWARF .debug_info

[macabeus]

What

Adds DWARF type information to @gba-kit/debug-info and surfaces it in the scripting engine, so scripts and tests can read struct fields by name instead of hand-maintained addresses, offsets, and masks.

@gba-kit/debug-info

• struct(name) — struct/union layout: members with byte offsets and sizes (descends anonymous unions/structs).
• structMember(name, path) / variableMember(symbol, path) — resolve a dotted/array field path to its { offset, size, bitOffset?, bitWidth? }, rooted at a type name or at a global (whose type is read from its own DWARF DIE).
• resolveVariable("symbol.field") — one call to a ResolvedLocation (address from .symtab, layout from DWARF).
• enumValues(name), hasTypeInfo; exports TypeIndex, ResolvedLocation, MemberLocation.
• Bitfields report bitOffset/bitWidth; members whose size can't be determined (incomplete type, flexible array) report size: null.
• symbolToAddress now also resolves absolute (SHN_ABS) STT_NOTYPE ldscript globals (gFoo = 0x...;), while excluding section-relative markers (_end, __bss_start).
• Parses DWARF 2–5 (agbcc and modern GCC), including multi-CU abbrev tables; malformed input degrades gracefully rather than crashing the load.

Scripting (@gba-kit/gba-emulator, @gba-kit/gba-node)

• readVariable(path) — read a global or symbol.field by name, sized and bitfield-decoded from the DWARF (the read counterpart to watchSymbol).
• wait({ memory }) and assert({ memory }) — address now also accepts a symbol/symbol.field path (read at the field's full width), in addition to a raw numeric address.

await wait({ memory: { address: 'game_sm.state', equals: 5 } });
const score = readVariable('g_game_vars.score');

Tests

Real ELF fixtures from both toolchains (agbcc DWARF-2, devkitARM DWARF-5) assert struct/enum/bitfield layouts, nested + anonymous-union member paths, multi-CU resolution, flexible arrays, and ldscript-symbol in/exclusion.