style: unify identifier naming per updated conventions

Automated with clang-tidy readability-identifier-naming (config added to
.clang-tidy) plus scripted passes, per the updated rules now documented
in CONTRIBUTING.md:

- types (class/struct/enum/alias/template params): PascalCase
- functions, variables, members: snake_case (incl. rational -> Rational)
- private/protected members: trailing underscore; static member
  variables likewise (instance_, available_themes_)
- constants and enum values: snake_case (kLinear -> k_linear,
  F32P -> f32p); ALL_CAPS reserved for macros
- macros: OAK_ prefix (OLIVE_ADD_TEST/OLIVE_ASSERT/OLIVE_CONFIG ->
  OAK_ADD_TEST/OAK_ASSERT/OAK_CONFIG, GL_PREAMBLE -> OAK_GL_PREAMBLE,
  include guards -> OAK_*)
- file names: all lowercase (Current/Plugin/OliveHost/OliveClip/
  OlivePluginInstance -> current/plugin/olivehost/oliveclip/
  oliveplugininstance)
- getters share the member name sans underscore, setters set_foo()
- Qt and third-party (OpenFX) virtual overrides and framework callbacks
  keep their original names (exempt in .clang-tidy)

Manual follow-ups required where automation could not reach:
- string-based QMetaObject/SIGNAL/SLOT references updated to renamed
  methods (AddTask, CreatedFile, DeleteSpecificFile, moveSelectionUp, ...)
- macro bodies referencing renamed methods (OLIVE_CONFIG,
  NODE_DEFAULT_DESTRUCTOR, MANAGEDDISPLAYWIDGET_*)
- self-shadowing locals renamed where signals/methods became same-named
  (size_changed, worker_count, selected_items, import param, filters)
- third_party OFX member/namespace usages restored (OFX::Host::*,
  _created, _clipPrefsDirty, createInstance, clearPersistentMessage)
- STL protocol aliases restored (const_iterator) with .clang-tidy
  ignore rules; qHash overloads restored

Full build and test suite pass: ctest 4/4, ~1960 gtest cases green.

app/node/generator/solid/solid.cpp

@@ -24,18 +24,18 @@
 namespace olive
 {
 
-const QString SolidGenerator::kColorInput = QStringLiteral("color_in");
+const QString SolidGenerator::k_color_input = QStringLiteral("color_in");
 
 #define super Node
 
 SolidGenerator::SolidGenerator()
 {
 	// Default to a color that isn't black
-	AddInput(kColorInput, NodeValue::kColor,
+	add_input(k_color_input, NodeValue::k_color,
 			 QVariant::fromValue(Color(1.0f, 0.0f, 0.0f, 1.0f)));
 }
 
-QString SolidGenerator::Name() const
+QString SolidGenerator::name() const
 {
 	return tr("Solid");
 }
@@ -45,36 +45,36 @@ QString SolidGenerator::id() const
 	return QStringLiteral("org.olivevideoeditor.Olive.solidgenerator");
 }
 
-QVector<Node::CategoryID> SolidGenerator::Category() const
+QVector<Node::CategoryID> SolidGenerator::category() const
 {
-	return { kCategoryGenerator };
+	return { k_category_generator };
 }
 
-QString SolidGenerator::Description() const
+QString SolidGenerator::description() const
 {
 	return tr("Generate a solid color.");
 }
 
-void SolidGenerator::Retranslate()
+void SolidGenerator::retranslate()
 {
-	super::Retranslate();
+	super::retranslate();
 
-	SetInputName(kColorInput, tr("Color"));
+	set_input_name(k_color_input, tr("Color"));
 }
 
-void SolidGenerator::Value(const NodeValueRow &value,
+void SolidGenerator::value(const NodeValueRow &value,
 						   const NodeGlobals &globals,
 						   NodeValueTable *table) const
 {
-	table->Push(NodeValue::kTexture,
-				Texture::Job(globals.vparams(), ShaderJob(value)), this);
+	table->push(NodeValue::k_texture,
+				Texture::job(globals.vparams(), ShaderJob(value)), this);
 }
 
-ShaderCode SolidGenerator::GetShaderCode(const ShaderRequest &request) const
+ShaderCode SolidGenerator::get_shader_code(const ShaderRequest &request) const
 {
 	Q_UNUSED(request)
 
-	return ShaderCode(FileFunctions::ReadFileAsString(":/shaders/solid.frag"));
+	return ShaderCode(FileFunctions::read_file_as_string(":/shaders/solid.frag"));
 }
 
 }