Refactor create_event_modal into modular components

- Split massive 27K line modal into focused components
- Created event_form module with 6 tab components:
  * BasicDetailsTab - main event info with recurrence options properly positioned
  * AdvancedTab - status, privacy, priority
  * PeopleTab - organizer and attendees
  * CategoriesTab - event categories
  * LocationTab - location information
  * RemindersTab - reminder settings
- Added shared types and data structures
- Created new CreateEventModalV2 using modular architecture
- Recurrence options now positioned directly after repeat/reminder pickers

🤖 Generated with [Claude Code](https://claude.ai/code)

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

frontend/src/components/event_form/people.rs

@@ -0,0 +1,63 @@
+use super::types::*;
+use wasm_bindgen::JsCast;
+use web_sys::{HtmlInputElement, HtmlTextAreaElement};
+use yew::prelude::*;
+
+#[function_component(PeopleTab)]
+pub fn people_tab(props: &TabProps) -> Html {
+    let data = &props.data;
+    
+    let on_organizer_input = {
+        let data = data.clone();
+        Callback::from(move |e: InputEvent| {
+            if let Some(target) = e.target() {
+                if let Ok(input) = target.dyn_into::<HtmlInputElement>() {
+                    let mut event_data = (*data).clone();
+                    event_data.organizer = input.value();
+                    data.set(event_data);
+                }
+            }
+        })
+    };
+
+    let on_attendees_input = {
+        let data = data.clone();
+        Callback::from(move |e: InputEvent| {
+            if let Some(target) = e.target() {
+                if let Ok(textarea) = target.dyn_into::<HtmlTextAreaElement>() {
+                    let mut event_data = (*data).clone();
+                    event_data.attendees = textarea.value();
+                    data.set(event_data);
+                }
+            }
+        })
+    };
+
+    html! {
+        <div class="tab-panel">
+            <div class="form-group">
+                <label for="event-organizer">{"Organizer"}</label>
+                <input
+                    type="text"
+                    id="event-organizer"
+                    class="form-input"
+                    value={data.organizer.clone()}
+                    oninput={on_organizer_input}
+                    placeholder="Event organizer"
+                />
+            </div>
+
+            <div class="form-group">
+                <label for="event-attendees">{"Attendees"}</label>
+                <textarea
+                    id="event-attendees"
+                    class="form-input"
+                    value={data.attendees.clone()}
+                    oninput={on_attendees_input}
+                    placeholder="Add attendees (one per line)"
+                    rows="4"
+                ></textarea>
+            </div>
+        </div>
+    }
+}