feat: productivity suite — task loop, workflow, theming, docs & more (#197)

## Summary

A large productivity-focused feature branch delivering a suite of improvements across automation, project management, theming, performance, and documentation.

### Features

- **Guided Project Workflow** (#189) — Four-phase workflow panel (Discuss → Plan → Execute → Verify) to keep projects structured from idea to completion
- **Automated Task Loop** (#179) — Per-task conversation orchestration with wave-based parallel execution, blocked-task detection, and concurrency control
- **Wave-Based Parallel Execution** (#191) — Tasks run in dependency-aware waves with configurable concurrency; independent tasks execute in parallel
- **Auto-Commit After Task Completion** (#192) — Task Loop optionally commits after each completed task so progress is never lost
- **PRD Creator** (#180) — AI-assisted PRD and task list panel that outputs `hikari-tasks.json` for the Task Loop to consume
- **Project Context Panel** (#188) — Persistent `PROJECT.md`, `REQUIREMENTS.md`, `ROADMAP.md`, and `STATE.md` files injected into Claude's context automatically
- **Codebase Mapper** (#190) — Generates a `CODEBASE.md` architectural summary so Claude always understands the project structure
- **Community Preset Themes** (#181) — Six built-in community themes: Dracula, Catppuccin Mocha, Nord, Solarized Dark, Gruvbox Dark, and Rosé Pine
- **In-App Changelog Panel** (#193) — Fetches release notes from GitHub at runtime and displays them inside the app
- **Full Embedded Documentation** (#196) — Replaced the single-page help modal with a 12-page paginated docs browser featuring a sidebar TOC, prev/next navigation, keyboard navigation (arrow keys, `?` shortcut), and comprehensive coverage of every feature

### Performance & Fixes

- **Lazy Loading & Virtualisation** (#194) — Virtual windowing for conversation history, markdown memoisation, and debounced search for smooth rendering of large sessions
- **Ctrl+C Copy Fix** (#195) — `Ctrl+C` now copies selected text as expected; interrupt-Claude behaviour only fires when no text is selected

### UX

- Back-to-workflow button in PRD Creator and Task Loop panels for easy navigation
- Navigation icon cluster replaced with a single clean dropdown menu

## Closes

Closes #179
Closes #180
Closes #181
Closes #188
Closes #189
Closes #190
Closes #191
Closes #192
Closes #193
Closes #194
Closes #195
Closes #196

---

✨ This PR was created with help from Hikari~ 🌸

Reviewed-on: #197
Co-authored-by: Hikari <hikari@nhcarrigan.com>
Co-committed-by: Hikari <hikari@nhcarrigan.com>

src/lib/stores/config.test.ts

@@ -217,6 +217,9 @@ describe("config store", () => {
         custom_font_family: null,
         custom_ui_font_path: null,
         custom_ui_font_family: null,
+        task_loop_auto_commit: false,
+        task_loop_commit_prefix: "feat",
+        task_loop_include_summary: false,
       };
 
       expect(config.model).toBe("claude-sonnet-4");
@@ -273,6 +276,9 @@ describe("config store", () => {
         custom_font_family: null,
         custom_ui_font_path: null,
         custom_ui_font_family: null,
+        task_loop_auto_commit: false,
+        task_loop_commit_prefix: "feat",
+        task_loop_include_summary: false,
       };
 
       expect(config.model).toBeNull();
@@ -337,6 +343,62 @@ describe("config store", () => {
       expect(document.documentElement.getAttribute("data-theme")).toBe("dark");
     });
 
+    it("sets data-theme attribute for dracula theme", () => {
+      applyTheme("dracula");
+      expect(document.documentElement.getAttribute("data-theme")).toBe("dracula");
+    });
+
+    it("sets data-theme attribute for catppuccin theme", () => {
+      applyTheme("catppuccin");
+      expect(document.documentElement.getAttribute("data-theme")).toBe("catppuccin");
+    });
+
+    it("sets data-theme attribute for nord theme", () => {
+      applyTheme("nord");
+      expect(document.documentElement.getAttribute("data-theme")).toBe("nord");
+    });
+
+    it("sets data-theme attribute for solarized theme", () => {
+      applyTheme("solarized");
+      expect(document.documentElement.getAttribute("data-theme")).toBe("solarized");
+    });
+
+    it("sets data-theme attribute for solarized-light theme", () => {
+      applyTheme("solarized-light");
+      expect(document.documentElement.getAttribute("data-theme")).toBe("solarized-light");
+    });
+
+    it("sets data-theme attribute for catppuccin-latte theme", () => {
+      applyTheme("catppuccin-latte");
+      expect(document.documentElement.getAttribute("data-theme")).toBe("catppuccin-latte");
+    });
+
+    it("sets data-theme attribute for gruvbox-light theme", () => {
+      applyTheme("gruvbox-light");
+      expect(document.documentElement.getAttribute("data-theme")).toBe("gruvbox-light");
+    });
+
+    it("sets data-theme attribute for rose-pine-dawn theme", () => {
+      applyTheme("rose-pine-dawn");
+      expect(document.documentElement.getAttribute("data-theme")).toBe("rose-pine-dawn");
+    });
+
+    it("does not apply custom colors for preset themes", () => {
+      const colors: CustomThemeColors = {
+        bg_primary: "#ff0000",
+        bg_secondary: null,
+        bg_terminal: null,
+        accent_primary: null,
+        accent_secondary: null,
+        text_primary: null,
+        text_secondary: null,
+        border_color: null,
+      };
+
+      applyTheme("dracula", colors);
+      expect(document.documentElement.style.getPropertyValue("--bg-primary")).toBe("");
+    });
+
     it("applies custom colors when theme is custom", () => {
       const colors: CustomThemeColors = {
         bg_primary: "#1a1a2e",
@@ -828,6 +890,9 @@ describe("config store", () => {
         custom_font_family: null,
         custom_ui_font_path: null,
         custom_ui_font_family: null,
+        task_loop_auto_commit: false,
+        task_loop_commit_prefix: "feat",
+        task_loop_include_summary: false,
       };
 
       const mockInvokeImpl = vi.mocked(invoke);