[JamieW105]

C playtest validation fails on Windows because the SDK's two strcpy calls trigger CRT deprecation warnings under -Werror. Copy the saved callback source with memcpy and strlen + 1 in both directions, preserving the terminating NUL and existing buffer sizes without suppressing compiler warnings.

Validation:

• Reproduced both original errors using a GCC deprecation declaration matching the Windows CRT diagnostic.
• Compiled the fixed C starter with C17, -Wall -Wextra -Werror, and the same deprecation declaration.
• Exercised repeated live queries with short and near-limit UTF-8 callback snapshots; verified source restoration, snapshot reads, and command flush order.
• git diff --check passed.

Remaining validation: native Windows playtest and installer build. The required powershell -ExecutionPolicy Bypass -File ./tools/build-windows-installer.ps1 attempt failed because PowerShell is unavailable in this Linux workspace; no installer was produced. Cargo is also unavailable, so Rust tests could not run. Kept as draft pending Windows validation.