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.

1 files changed, 36 insertions, 0 deletions

diff --git a/src/tests/test_window.cc b/src/tests/test_window.cc
new file mode 100644
index 0000000..e23d97c
--- /dev/null
+++ b/src/tests/test_window.cc
@@ -0,0 +1,36 @@
+#include "audio/window.h"
+#include <assert.h>
+#include <math.h>
+#include <stdio.h>
+
+// A simple floating point comparison with a tolerance
+bool is_close(float a, float b, float epsilon = 1e-6f) {
+  return fabsf(a - b) < epsilon;
+}
+
+int main() {
+  float window[WINDOW_SIZE];
+  hamming_window_512(window);
+
+  // Test 1: Window should start and end at the same small value
+  assert(is_close(window[0], 0.08f));
+  assert(is_close(window[WINDOW_SIZE - 1], 0.08f));
+  printf("Test 1 passed: Window start and end values are correct.\n");
+
+  // Test 2: Window should be symmetric
+  for (int i = 0; i < WINDOW_SIZE / 2; ++i) {
+    assert(is_close(window[i], window[WINDOW_SIZE - 1 - i]));
+  }
+  printf("Test 2 passed: Window is symmetric.\n");
+
+  // Test 3: The two middle points of the even-sized window should be equal and
+  // the peak.
+  assert(is_close(window[WINDOW_SIZE / 2 - 1], window[WINDOW_SIZE / 2]));
+  assert(window[WINDOW_SIZE / 2] >
+         window[WINDOW_SIZE / 2 - 2]); // Should be greater than neighbors
+  printf("Test 3 passed: Window peak is correct for even size.\n");
+
+  printf("All tests passed for Hamming window!\n");
+
+  return 0;
+}