Add side panels, task selection, graph animation, and project docs

- Foldable left panel (user profile) and right panel (task details)
- Clicking a task in the list or graph node selects it and shows details
- Both views (task list + graph) always mounted via absolute inset-0 for
  correct canvas dimensions; tabs toggle visibility with opacity
- Graph node selection animation: other nodes repel outward (charge -600),
  then selected node smoothly slides to center (500ms cubic ease-out),
  then charge restores to -120 and graph stabilizes
- Graph re-fits on tab switch and panel resize via ResizeObserver
- Fix UUID string IDs throughout (backend returns UUIDs, not integers)
- Add TaskDetailPanel, UserPanel components
- Add CLAUDE.md project documentation

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

frontend/node_modules/parse-json/index.js

@@ -0,0 +1,54 @@
+'use strict';
+const errorEx = require('error-ex');
+const fallback = require('json-parse-even-better-errors');
+const {default: LinesAndColumns} = require('lines-and-columns');
+const {codeFrameColumns} = require('@babel/code-frame');
+
+const JSONError = errorEx('JSONError', {
+	fileName: errorEx.append('in %s'),
+	codeFrame: errorEx.append('\n\n%s\n')
+});
+
+const parseJson = (string, reviver, filename) => {
+	if (typeof reviver === 'string') {
+		filename = reviver;
+		reviver = null;
+	}
+
+	try {
+		try {
+			return JSON.parse(string, reviver);
+		} catch (error) {
+			fallback(string, reviver);
+			throw error;
+		}
+	} catch (error) {
+		error.message = error.message.replace(/\n/g, '');
+		const indexMatch = error.message.match(/in JSON at position (\d+) while parsing/);
+
+		const jsonError = new JSONError(error);
+		if (filename) {
+			jsonError.fileName = filename;
+		}
+
+		if (indexMatch && indexMatch.length > 0) {
+			const lines = new LinesAndColumns(string);
+			const index = Number(indexMatch[1]);
+			const location = lines.locationForIndex(index);
+
+			const codeFrame = codeFrameColumns(
+				string,
+				{start: {line: location.line + 1, column: location.column + 1}},
+				{highlightCode: true}
+			);
+
+			jsonError.codeFrame = codeFrame;
+		}
+
+		throw jsonError;
+	}
+};
+
+parseJson.JSONError = JSONError;
+
+module.exports = parseJson;