M1 step 5: IRC App

- Chat: header (Buffer n/N, unread elsewhere, topic or connection
  state), wrapped hh:mm <nick> lines (own in accent, Mentions green,
  info grey), input line; Tab cycles Buffers, Fn+Up/Down scrolls back,
  Enter sends, Back leaves while the IRC Service keeps running
- /settings: server form (host, port, TLS, self-signed pinning, nick,
  SASL, NickServ, auto-join); Save & reconnect restarts the session
- Opening the App starts the IRC Service; viewing a Buffer clears its
  unread count; IrcSession gains a revision counter for redraws

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01EhqxQ49eCju4CzKYNjZzwT

src/apps/irc_app.h

@@ -0,0 +1,55 @@
+#pragma once
+
+#include <string>
+
+#include "app.h"
+#include "event_bus.h"
+#include "line_editor.h"
+#include "list_model.h"
+#include "services/irc_service.h"
+#include "ui/theme.h"
+
+namespace roro {
+
+// IRC: one Buffer at a time with an input line; /settings opens the server form. Opening the App
+// starts the IRC Service, which keeps running after the App is left.
+class IrcApp : public App {
+   public:
+    IrcApp(IrcService& irc, ClockService& clock, EventBus& bus) : irc_(irc), clock_(clock), bus_(bus) {}
+    void onEnter() override;
+    void onExit() override;
+    bool onKey(const KeyEvent& e) override;
+    void update(uint32_t nowMs) override;
+    bool textEntryActive() const override { return page_ == Page::Chat || editing_; }
+    void draw(Canvas& c) override;
+
+   private:
+    enum class Page { Chat, Settings };
+    enum Field { kHost, kPort, kTls, kSelfSigned, kNick, kSaslUser, kSaslPass, kNickserv, kAutojoin, kSave, kFields };
+
+    bool onChatKey(const KeyEvent& e);
+    bool onSettingsKey(const KeyEvent& e);
+    void view(int buffer);
+    void drawChat(Canvas& c);
+    void drawSettings(Canvas& c);
+    std::string fieldLabel(int f) const;
+    std::string fieldValue(int f) const;
+    void startEditing(int f);
+    void finishEditing();
+    void warn(const std::string& text);
+
+    IrcService& irc_;
+    ClockService& clock_;
+    EventBus& bus_;
+    Page page_ = Page::Chat;
+    int current_ = 0;
+    int scroll_ = 0;  // wrapped lines scrolled back from the bottom
+    uint32_t seenRevision_ = 0;
+    IrcService::Status seenStatus_ = IrcService::Status::Stopped;
+    LineEditor input_{400};
+    ListModel fields_{theme::kContent.h / theme::kLineHeight};
+    bool editing_ = false;
+    LineEditor fieldEditor_{63};
+};
+
+}  // namespace roro