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, 34 insertions, 27 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5f1167f..92d12f2 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -7,14 +7,14 @@ set(CMAKE_CXX_STANDARD 17)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)
 
 add_executable(demo64k
-    src/main.cpp
-    src/platform.cpp
-    src/gpu/gpu.cpp
-    src/audio/audio.cpp
-    src/audio/fdct.cpp
-    src/audio/idct.cpp
-    src/audio/window.cpp
-    src/audio/synth.cpp
+    src/main.cc
+    src/platform.cc
+    src/gpu/gpu.cc
+    src/audio/audio.cc
+    src/audio/fdct.cc
+    src/audio/idct.cc
+    src/audio/window.cc
+    src/audio/synth.cc
 )
 
 target_include_directories(demo64k PRIVATE
@@ -40,8 +40,8 @@ enable_testing()
 
 if(DEMO_BUILD_TESTS)
     add_executable(test_window
-        src/tests/test_window.cpp
-        src/audio/window.cpp
+        src/tests/test_window.cc
+        src/audio/window.cc
     )
     target_include_directories(test_window PRIVATE
         src
@@ -49,10 +49,10 @@ if(DEMO_BUILD_TESTS)
     add_test(NAME HammingWindowTest COMMAND test_window)
 
     add_executable(test_synth
-        src/tests/test_synth.cpp
-        src/audio/synth.cpp
-        src/audio/idct.cpp
-        src/audio/window.cpp
+        src/tests/test_synth.cc
+        src/audio/synth.cc
+        src/audio/idct.cc
+        src/audio/window.cc
     )
     target_include_directories(test_synth PRIVATE
         src
@@ -60,12 +60,12 @@ if(DEMO_BUILD_TESTS)
     add_test(NAME SynthEngineTest COMMAND test_synth)
 
     add_executable(test_spectool
-        src/tests/test_spectool.cpp
-        src/audio/audio.cpp # For miniaudio implementation
-        src/audio/window.cpp
-        src/audio/fdct.cpp
-        src/audio/synth.cpp
-        src/audio/idct.cpp
+        src/tests/test_spectool.cc
+        src/audio/audio.cc # For miniaudio implementation
+        src/audio/window.cc
+        src/audio/fdct.cc
+        src/audio/synth.cc
+        src/audio/idct.cc
     )
     target_include_directories(test_spectool PRIVATE
         src
@@ -78,17 +78,24 @@ endif()
 option(DEMO_BUILD_TOOLS "Build tools" OFF)
 if(DEMO_BUILD_TOOLS)
     add_executable(spectool
-        tools/spectool.cpp
-        src/platform.cpp
-        src/audio/audio.cpp
-        src/audio/fdct.cpp
-        src/audio/idct.cpp
-        src/audio/window.cpp
-        src/audio/synth.cpp
+        tools/spectool.cc
+        src/platform.cc
+        src/audio/audio.cc
+        src/audio/fdct.cc
+        src/audio/idct.cc
+        src/audio/window.cc
+        src/audio/synth.cc
     )
     target_include_directories(spectool PRIVATE
         src
         third_party
     )
     target_link_libraries(spectool PRIVATE glfw)
+
+    add_executable(specview
+        tools/specview.cc
+    )
+    target_include_directories(specview PRIVATE
+        src
+    )
 endif()