refactor: move scattered business logic into domain

- CodeGraph::merge_project_edges() replaces presentation-layer function
- Language::is_test_file() centralises test file detection (was in walkdir)
- AnalysisConfig::is_standard_excluded() centralises default dir exclusions (was in walkdir)
- normalize_cargo_package() / normalize_python_package() in domain replace duplicated normalisers in each adapter
- walkdir, cargo-workspace, python-project updated to call domain methods

crates/presentation/src/lib.rs

@@ -9,7 +9,7 @@ use archlens_ascii::AsciiRenderer;
 use archlens_cargo_workspace::CargoWorkspaceAnalyzer;
 use archlens_d2::D2Renderer;
 use archlens_domain::{
-    BoundaryRule, CodeGraph, DiagramLevel, ModuleName, check_boundary_rules,
+    BoundaryRule, CodeGraph, DiagramLevel, check_boundary_rules,
     ports::{ConfigLoader, OutputWriter, ProjectAnalyzer},
 };
 use archlens_file_writer::FileOutputWriter;
@@ -154,7 +154,7 @@ fn build_graph(args: &Cli, level: DiagramLevel) -> Result<CodeGraph> {
             PythonProjectAnalyzer::new().analyze(&args.path).ok()
         };
         if let Some(pg) = project_graph {
-            merge_project_deps_as_module_edges(&mut graph, &pg);
+            graph.merge_project_edges(&pg);
         }
     }
 
@@ -265,49 +265,6 @@ fn write_single(
     Ok(())
 }
 
-fn merge_project_deps_as_module_edges(
-    graph: &mut archlens_domain::CodeGraph,
-    project_graph: &archlens_domain::CodeGraph,
-) {
-    use std::collections::HashMap;
-
-    let mut crate_to_module: HashMap<String, String> = HashMap::new();
-    for element in project_graph.elements() {
-        let module = if let Some(m) = element.module() {
-            m.as_str().to_string()
-        } else {
-            let path = element.file_path().as_str();
-            let dir = path.split('/').rev().nth(1).unwrap_or(element.name());
-            ModuleName::capitalize(dir)
-        };
-        crate_to_module.insert(element.name().to_string(), module);
-    }
-
-    let graph_modules: std::collections::HashSet<String> = graph
-        .modules()
-        .iter()
-        .map(|m| m.as_str().to_string())
-        .collect();
-
-    for rel in project_graph.relationships() {
-        let src_module = crate_to_module.get(rel.source());
-        let tgt_module = crate_to_module.get(rel.target());
-
-        if let (Some(src_cap), Some(tgt_cap)) = (src_module, tgt_module)
-            && src_cap != tgt_cap
-            && graph_modules.contains(src_cap)
-            && graph_modules.contains(tgt_cap)
-            && let Ok(edge) = archlens_domain::Relationship::new(
-                src_cap,
-                tgt_cap,
-                archlens_domain::RelationshipKind::Composition,
-            )
-        {
-            graph.add_relationship(edge);
-        }
-    }
-}
-
 fn run_diff(args: &Cli, existing_path: &std::path::Path) -> Result<()> {
     init_tracing(args.verbose);