[cellrishi-code]

Summary

This consolidated PR addresses the ten repository issues created after reviewing the current x86_64/no_std kernel, host QEMU runner, RAM filesystem prototype, memory-map summary, and CI workflow.

• Improve QEMU and OVMF error diagnostics; add unit tests for CLI parsing.
• Pin OVMF to EDK2 stable 202508-r1 for reproducible UEFI firmware selection.
• Publish RAM filesystem size limits and add boundary/path/content regression tests.
• Add synthetic tests for memory-map aggregation, empty maps, invalid ranges, and saturation.
• Add a troubleshooting guide and link it from the README.
• Define a stable [BOOT_OK] marker that is emitted only after early initialization and the RAM filesystem smoke check pass.
• Add a bounded QEMU BIOS boot smoke test that asserts the serial success marker.
• Install rust-src, required by the bootloader's build-std build, and format affected sources.

Issues addressed

Closes #87
Closes #88
Closes #89
Closes #90
Closes #91
Closes #92
Closes #93
Closes #94
Closes #95
Closes #96

Validation

The initial CI run found formatting issues and then failed because rust-src was missing for the bootloader's build-std step. Formatting has been corrected and rust-src has been added to the repository toolchain and QEMU job. Please use the latest GitHub Actions run as the verification source; I have not run the compiler or QEMU locally in this session.