refactor: modularize server.rs into separate route modules

- Extract scan.rs, files.rs, types.rs, processing.rs, visual_chunk_search.rs
- Move AppState and AppConfig to types.rs
- Each module exposes pub fn xxx_routes() -> Router<AppState>
- server.rs reduced from 5005 to 118 lines (orchestrator only)
- All stubs filled with real implementations from git history
- Verify: cargo check, clippy, tests all pass

src/api/docs.rs

@@ -0,0 +1,54 @@
+use axum::{extract::Path, http::StatusCode, routing::get, Router};
+
+use super::types::AppState;
+
+async fn doc_redirect() -> axum::response::Redirect {
+    axum::response::Redirect::to("/doc-wasm")
+}
+
+async fn wasm_doc_handler() -> Result<impl axum::response::IntoResponse, (StatusCode, &'static str)>
+{
+    let path =
+        std::path::Path::new("/Users/accusys/momentry_core_0.1/docs_v1.0/doc_wasm/index.html");
+    match tokio::fs::read_to_string(path).await {
+        Ok(html) => Ok(([("content-type", "text/html; charset=utf-8")], html)),
+        Err(_) => Err((StatusCode::NOT_FOUND, "Doc not found")),
+    }
+}
+
+async fn wasm_doc_file_handler(
+    Path(file): Path<String>,
+) -> Result<impl axum::response::IntoResponse, (StatusCode, &'static str)> {
+    if file.contains("..") || file.contains("//") {
+        return Err((StatusCode::NOT_FOUND, "Invalid path"));
+    }
+    let base = std::path::Path::new("/Users/accusys/momentry_core_0.1/docs_v1.0/doc_wasm");
+    let path = base.join(&file);
+    if !path.exists() || !path.starts_with(base) {
+        return Err((StatusCode::NOT_FOUND, "File not found"));
+    }
+    let data = tokio::fs::read(&path)
+        .await
+        .map_err(|_| (StatusCode::NOT_FOUND, "Read error"))?;
+    let mime = if file.ends_with(".wasm") {
+        "application/wasm"
+    } else if file.ends_with(".js") {
+        "application/javascript"
+    } else if file.ends_with(".md") {
+        "text/markdown; charset=utf-8"
+    } else if file.ends_with(".css") {
+        "text/css"
+    } else {
+        "application/octet-stream"
+    };
+    Ok(([("content-type", mime)], data))
+}
+
+pub fn doc_routes() -> Router<AppState> {
+    Router::new()
+        .route("/doc", get(doc_redirect))
+        .route("/doc/*file", get(doc_redirect))
+        .route("/dev-doc", get(doc_redirect))
+        .route("/doc-wasm", get(wasm_doc_handler))
+        .route("/doc-wasm/*file", get(wasm_doc_file_handler))
+}