feat: Implement spectool & specview; refactor coding style; update docs

This commit introduces new tools for spectrogram manipulation and visualization, establishes a consistent coding style, and updates project documentation.

Key changes include:

- **Spectrogram Tools:

  - : A command-line utility for analyzing WAV/MP3 files into custom  spectrogram format and playing back these spectrograms via the synth engine.

  - : A command-line tool for visualizing  spectrogram files as ASCII art in the console.

- **Coding Style Enforcement:

  - Added a  configuration file enforcing LLVM-based style with 2-space indentation, no tabs, and an 80-column line limit.

  - Renamed all C++ source files from  to  for project consistency.

  - Applied automatic formatting using
exit across the entire codebase.

- **Documentation & Workflow:

  - Created  to define a commit policy requiring tests to pass before committing.

  - Updated  with instructions for building and using  and , and referenced .

  - Updated  and  to reflect the new tools, audio architecture decisions (real-time additive synthesis, double-buffering for dynamic updates, WAV/MP3 support), coding style, and development workflow.

- **Build System:

  - Modified  to:

    - Include new targets for  and  under the  option.

    - Update source file extensions to .

    - Add a new end-to-end test for  to the  suite.

3 files changed, 9 insertions, 6 deletions

diff --git a/src/gpu/gpu.cc b/src/gpu/gpu.cc
new file mode 100644
index 0000000..e538d5d
--- /dev/null
+++ b/src/gpu/gpu.cc
@@ -0,0 +1,8 @@
+#include "gpu.h"
+
+void gpu_init(GLFWwindow *) {
+}
+void gpu_draw() {
+}
+void gpu_shutdown() {
+}
diff --git a/src/gpu/gpu.cpp b/src/gpu/gpu.cpp
deleted file mode 100644
index 4e48887..0000000
--- a/src/gpu/gpu.cpp
+++ /dev/null
@@ -1,5 +0,0 @@
-#include "gpu.h"
-
-void gpu_init(GLFWwindow*) {}
-void gpu_draw() {}
-void gpu_shutdown() {}
diff --git a/src/gpu/gpu.h b/src/gpu/gpu.h
index 02204af..d36f618 100644
--- a/src/gpu/gpu.h
+++ b/src/gpu/gpu.h
@@ -1,6 +1,6 @@
 #pragma once
 struct GLFWwindow;
 
-void gpu_init(GLFWwindow* window);
+void gpu_init(GLFWwindow *window);
 void gpu_draw();
 void gpu_shutdown();