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/components/docs/DocsSessionManagement.svelte

@@ -0,0 +1,80 @@
+<h3 class="text-lg font-semibold text-[var(--text-primary)] mb-4">Session Management</h3>
+
+<div class="space-y-4 text-sm text-[var(--text-secondary)]">
+  <div>
+    <h4 class="font-medium text-[var(--text-primary)] mb-2">Multiple Conversations</h4>
+    <p>
+      Use tabs at the top of the chat area to manage multiple simultaneous sessions with Hikari.
+    </p>
+    <ul class="space-y-1 mt-2">
+      <li>• Click <strong>+</strong> to open a new conversation tab</li>
+      <li>• Click a tab to switch between active conversations</li>
+      <li>• Click <strong>×</strong> on a tab to close that conversation</li>
+    </ul>
+    <p class="mt-2">
+      Each tab runs its own independent Claude Code session with separate context and history.
+    </p>
+  </div>
+
+  <div>
+    <h4 class="font-medium text-[var(--text-primary)] mb-2">Session History</h4>
+    <p>
+      Open <strong>Session History</strong> from the menu to browse and restore past conversations. Sessions
+      are saved automatically and indexed by date.
+    </p>
+  </div>
+
+  <div>
+    <h4 class="font-medium text-[var(--text-primary)] mb-2">Context Compaction</h4>
+    <p>
+      As conversations grow long, use <strong>Compact Conversation</strong> from the menu to summarise
+      the history and free up context window space — without losing important information.
+    </p>
+    <p class="mt-2">
+      <strong>Start Fresh with Context</strong> creates a brand-new session but carries over a summary
+      of the previous conversation.
+    </p>
+  </div>
+
+  <div>
+    <h4 class="font-medium text-[var(--text-primary)] mb-2">Tool Permissions</h4>
+    <p>
+      When Hikari needs to use a tool (file access, terminal, web fetch, etc.) she may ask for your
+      approval first. You can:
+    </p>
+    <ul class="space-y-1 mt-2">
+      <li>• <strong>Allow once</strong> — approve this single use</li>
+      <li>• <strong>Allow for session</strong> — approve all uses of this tool this session</li>
+      <li>• <strong>Deny</strong> — block the action</li>
+    </ul>
+  </div>
+
+  <div>
+    <h4 class="font-medium text-[var(--text-primary)] mb-2">Stats Panel</h4>
+    <p>
+      Open <strong>Stats</strong> from the menu to see real-time usage data: token counts, estimated cost,
+      context window usage, and per-session totals.
+    </p>
+  </div>
+
+  <div>
+    <h4 class="font-medium text-[var(--text-primary)] mb-2">Streamer Mode</h4>
+    <p>
+      Toggle streamer mode (<kbd class="kbd">Ctrl+Shift+S</kbd>) to redact your API key and other
+      sensitive information from the display — useful for streaming or screen sharing.
+    </p>
+  </div>
+</div>
+
+<style>
+  kbd.kbd {
+    display: inline-block;
+    padding: 0.1rem 0.35rem;
+    font-size: 0.75rem;
+    font-family: monospace;
+    background: var(--bg-secondary);
+    border: 1px solid var(--border-color);
+    border-radius: 3px;
+    color: var(--text-primary);
+  }
+</style>