## Why

The `whitemagic-foundation` review found WhiteMagic is a superset of GreyMagic and current BlackMagic, but **not yet of MemorySharp**. Three genuinely useful capabilities MemorySharp (and, for threads, current BlackMagic's `SThread`) shipped are missing from WhiteMagic:

1. **Thread control** — WhiteMagic calls `SuspendThread`/`ResumeThread` only *internally* inside `DllInjector` thread-hijack. There is no public surface to enumerate a target's threads, suspend/resume them, or **freeze** them for the duration of an edit. Freezing threads is table-stakes for memory editing/trainers (MemorySharp: `ThreadFactory`/`RemoteThread`/`FrozenThread`; BlackMagic: `SThread`).
2. **Memory-region query** — WhiteMagic changes page protection inline inside `Detour` but exposes no `VirtualQueryEx` region walk, no query-region-at-address, and no reusable scoped protection helper (MemorySharp: `RemoteRegion`/`MemoryProtection`). Callers cannot inspect what is mapped, its protection, or safely flip protection around a write.
3. **Process discovery** — no way to open a target by name/window/title; the caller must obtain a PID out of band (MemorySharp: `ApplicationFinder`).

These are all **additive, low-risk** surfaces that sit on the existing `MemoryBase`/`SafeMemoryHandle` and native P/Invoke layer. None requires the deferred managed-loader work.

## What Changes

- **Thread control** (new capability `thread-control`): `RemoteThread` (open by id, suspend/resume, get/set context, get TEB, join), `ThreadFactory` (enumerate the target's threads, get main thread, get-by-id), and `FrozenThread`/`Freeze()` returning an `IDisposable` scope that suspends a set of threads and resumes them on dispose.
- **Memory-region query** (new capability `memory-region`): `MemoryRegion` (a queried `VirtualQueryEx` result — base, size, protection, state, type), region enumeration across the target's address space, query-region-containing-an-address, and a `ChangeProtection(...)` helper returning an `IDisposable` scope that restores the original protection on dispose.
- **Process discovery** (added to existing capability `high-level-api`): an `ApplicationFinder`/`Magic.Open` overloads to attach by process name, window title, or window handle, plus enumeration of candidate processes.

No behavior of existing WhiteMagic types changes; these are new types plus additive `Magic` facade members and new native imports.

## Capabilities

### New Capabilities
- `thread-control`: Enumerate, suspend/resume, freeze (scoped), and read/write the context of a target process's threads.
- `memory-region`: Query and enumerate mapped memory regions (`VirtualQueryEx`) and change page protection through a scoped, auto-restoring helper.

### Modified Capabilities
- `high-level-api`: Adds process discovery — attach a target by name/window/handle and enumerate candidates.

## Impact

- **New code**: `WhiteMagic/Thread/RemoteThread.cs`, `ThreadFactory.cs`, `FrozenThread.cs`; `WhiteMagic/Memory/MemoryRegion.cs`, `MemoryRegionEnumerator` (or methods on `MemoryBase`), `ProtectionScope`; `WhiteMagic/Process/ApplicationFinder.cs`; additive `Magic` facade members.
- **New native imports**: `Thread32First`/`Thread32Next` + `CreateToolhelp32Snapshot` (or `NtQueryInformationProcess` thread walk), `VirtualQueryEx`, `MEMORY_BASIC_INFORMATION`. `OpenThread`/`Suspend`/`Resume`/`Get`/`SetThreadContext` already exist in `NativeMethods`.
- **No dependency change**: pure P/Invoke over the existing core. No FASM, no Iced, no managed loader.
- **No changes** to BlackMagic/MemorySharp/GreyMagic or their tests.
- **Platform**: unchanged — bitness-agnostic (x86 + x64); thread context read honors the target's bitness like the existing hijack path.