fix: Resolve web package lint and typecheck errors

Fixes ESLint and TypeScript errors in web package to pass CI checks:

- Fixed all Quality Rails violations (14 explicit any types)
- Fixed deprecated React event types (FormEvent → SyntheticEvent)
- Fixed 26 TypeScript errors (Promise types, test mocks, HTMLElement assertions)
- Added vitest DOM matcher type definitions
- Fixed unused variables and empty functions
- Resolved 43+ additional lint errors

Typecheck: ✅ 0 errors
Lint: 542 remaining (non-blocking in CI)

Co-Authored-By: Claude Sonnet 4.5 <noreply@anthropic.com>

apps/web/src/components/knowledge/ImportExportActions.tsx

@@ -80,7 +80,7 @@ export function ImportExportActions({
       if (result.imported > 0 && onImportComplete) {
         onImportComplete();
       }
-    } catch (_error) {
+    } catch (error) {
       console.error("Import error:", error);
       alert(error instanceof Error ? error.message : "Failed to import file");
       setShowImportDialog(false);
@@ -135,7 +135,7 @@ export function ImportExportActions({
       a.click();
       window.URL.revokeObjectURL(url);
       document.body.removeChild(a);
-    } catch (_error) {
+    } catch (error) {
       console.error("Export error:", error);
       alert("Failed to export entries");
     } finally {

apps/web/src/components/knowledge/LinkAutocomplete.tsx

@@ -8,7 +8,7 @@ interface LinkAutocompleteProps {
   /**
    * The textarea element to attach autocomplete to
    */
-  textareaRef: React.RefObject<HTMLTextAreaElement>;
+  textareaRef: React.RefObject<HTMLTextAreaElement | null>;
   /**
    * Callback when a link is selected
    */
@@ -82,7 +82,7 @@ export function LinkAutocomplete({
 
       setResults(searchResults);
       setSelectedIndex(0);
-    } catch (_error) {
+    } catch (error) {
       console.error("Failed to search entries:", error);
       setResults([]);
     } finally {
@@ -116,7 +116,7 @@ export function LinkAutocomplete({
       const styles = window.getComputedStyle(textarea);
 
       // Copy relevant styles
-      [
+      const stylesToCopy = [
         "fontFamily",
         "fontSize",
         "fontWeight",
@@ -127,10 +127,13 @@ export function LinkAutocomplete({
         "boxSizing",
         "whiteSpace",
         "wordWrap",
-      ].forEach((prop) => {
-        mirror.style[prop as keyof CSSStyleDeclaration] = styles[
-          prop as keyof CSSStyleDeclaration
-        ] as string;
+      ] as const;
+
+      stylesToCopy.forEach((prop) => {
+        const value = styles.getPropertyValue(prop);
+        if (value) {
+          mirror.style.setProperty(prop, value);
+        }
       });
 
       mirror.style.position = "absolute";

apps/web/src/components/knowledge/__tests__/EntryEditor.test.tsx

@@ -31,7 +31,7 @@ describe("EntryEditor", (): void => {
     const content = "# Test Content\n\nThis is a test.";
     render(<EntryEditor {...defaultProps} content={content} />);
 
-    const textarea = screen.getByPlaceholderText(/Write your content here/);
+    const textarea = screen.getByPlaceholderText(/Write your content here/) as HTMLTextAreaElement;
     expect(textarea.value).toBe(content);
   });
 
@@ -112,7 +112,7 @@ describe("EntryEditor", (): void => {
     render(<EntryEditor {...defaultProps} content={content} />);
 
     // Verify content in edit mode
-    const textarea = screen.getByPlaceholderText(/Write your content here/);
+    const textarea = screen.getByPlaceholderText(/Write your content here/) as HTMLTextAreaElement;
     expect(textarea.value).toBe(content);
 
     // Toggle to preview
@@ -121,7 +121,7 @@ describe("EntryEditor", (): void => {
 
     // Toggle back to edit
     await user.click(screen.getByText("Edit"));
-    const textareaAfter = screen.getByPlaceholderText(/Write your content here/);
+    const textareaAfter = screen.getByPlaceholderText(/Write your content here/) as HTMLTextAreaElement;
     expect(textareaAfter.value).toBe(content);
   });
 

apps/web/src/components/knowledge/__tests__/LinkAutocomplete.test.tsx

@@ -380,7 +380,12 @@ describe("LinkAutocomplete", (): void => {
     const searchPromise = new Promise((resolve) => {
       resolveSearch = resolve;
     });
-    mockApiGet.mockReturnValue(searchPromise as Promise<any>);
+    mockApiGet.mockReturnValue(
+      searchPromise as Promise<{
+        data: unknown[];
+        meta: { total: number; page: number; limit: number; totalPages: number };
+      }>
+    );
 
     render(<LinkAutocomplete textareaRef={textareaRef} onInsert={onInsertMock} />);
 

apps/web/src/components/knowledge/index.ts

@@ -7,3 +7,4 @@ export { EntryEditor } from "./EntryEditor";
 export { EntryMetadata } from "./EntryMetadata";
 export { VersionHistory } from "./VersionHistory";
 export { ImportExportActions } from "./ImportExportActions";
+export { StatsDashboard } from "./StatsDashboard";