Write initial README with project overview, build instructions, and MVP scope #5

Description

Create a comprehensive README.md that serves as the project's front page.
This is the first thing reviewers (and hiring managers) will see, so it must clearly communicate the project's value, technical depth, and professionalism.

Sections

1. Project Title & Badge Bar

Include:

• GitHub Actions CI badge (from Issue 3, once working)
• License badge (MIT)
• C++20 badge
• Brief one-liner:

"Performance forensics and optimization toolkit for CPU-bound HPC workloads"

2. Overview (2–3 paragraphs)

Include:

• Problem statement:
  • Developers struggle to bridge application behavior with CPU architecture bottlenecks
• CPUScope approach:
  • Automated profiling
  • Bottleneck detection
  • Actionable optimization suggestions
• Target audience:
  • HPC developers
  • Performance engineers
  • System architects
• Mention alignment with Developer Technology engineering responsibilities

3. Key Features

Bullet list (each linked to implementation status):

• Low-level profiling via Linux perf and hardware counters
• Bottleneck detection (cache, branch, SIMD, threading)
• Optimization advisor with actionable hints
• Reference optimized kernels with before/after comparisons
• Reproducible benchmark harness with scaling analysis
• CPU architecture detection and dynamic adaptation

4. MVP Scope

Include a table:

Rules:

• Currently all features marked as 🚧 (in progress)
• Link to GitHub issue tracker for full roadmap

5. Quick Start

Include:

Prerequisites

• CMake ≥ 3.20
• GCC ≥ 13 or Clang ≥ 17
• Linux 5.x+
• perf permissions

Clone & Build (copy-paste ready)

Run tests

Run first benchmark

Placeholder command:

./build/cpuscope_cli run spmv --size 1000