glfw_live: --no-hdpi-framebuffer flag for matching framebuffer to logical size

[borisbat]

Summary

Adds a lazy-parsed CLI flag --no-hdpi-framebuffer (after the daslang -- separator) to modules/dasGlfw/dasglfw/glfw_live.das. When set, live_create_window sets two GLFW hints before glfwCreateWindow:

• GLFW_COCOA_RETINA_FRAMEBUFFER = 0 — macOS: disable retina backing, framebuffer == window size in physical pixels
• GLFW_SCALE_TO_MONITOR = 0 — Windows: don't auto-scale by monitor DPI (overrides any caller-set =1 hint)

Linux is unaffected — X11 doesn't apply scaling at the GLFW level; on Wayland the compositor reports framebuffer == window size for normal windows already.

Why

Companion to dasImgui's with_recording_app helper (PR borisbat/dasImgui#TBD). The recording helper passes BOTH --imgui-content-scale=1.0 (ImGui-side style scaling) and --no-hdpi-framebuffer (GLFW-side framebuffer size) so glReadPixels-based APNG capture stays at logical pixel count.

Without this flag: a 640×320-logical recording window opens at 1280×640 framebuffer on retina, quadrupling capture pixel count + PNG encoder workload. The APNG file size balloons (~28 MB vs ~8 MB) and the encoder can't keep up with the GL output rate (frames drop, recording lags).

Tutorial users running daslang-live directly pass neither flag and keep their native HDPI experience.

Test plan

• Compile + lint clean (mcp__daslang__compile_check / mcp__daslang__lint)
• Verified end-to-end on retina mac: daslang record_boost_basics.das (which spawns daslang-live with both flags) produces a 640×320 APNG (~7.8 MB) instead of 1280×640 (~28 MB)
• Daslang-live launched WITHOUT the flag still opens retina-backed framebuffer (HDPI tutorials unchanged)
• CI: cross-platform matrix green

🤖 Generated with Claude Code

[Copilot]

Pull request overview

Adds a lazy-parsed --no-hdpi-framebuffer CLI flag (after the daslang -- separator) to glfw_live. When set, live_create_window issues two GLFW hints before window creation (GLFW_COCOA_RETINA_FRAMEBUFFER=0 and GLFW_SCALE_TO_MONITOR=0) so the framebuffer matches the logical window size, primarily to keep APNG recording captures small.

Changes:

• Adds daslib/clargs import and lazy parse helpers (g_no_hdpi_parsed, g_no_hdpi, ensure_no_hdpi_parsed).
• In live_create_window, after glfwInitOpenGL and before glfwCreateWindow, applies the two GLFW hints when the flag is set.
• Documents the new flag in the function's //! block.

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