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/location.rs

@@ -0,0 +1,39 @@
+use super::types::*;
+use wasm_bindgen::JsCast;
+use web_sys::HtmlInputElement;
+use yew::prelude::*;
+
+#[function_component(LocationTab)]
+pub fn location_tab(props: &TabProps) -> Html {
+    let data = &props.data;
+    
+    let on_location_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.location = input.value();
+                    data.set(event_data);
+                }
+            }
+        })
+    };
+
+    html! {
+        <div class="tab-panel">
+            <div class="form-group">
+                <label for="event-location">{"Location"}</label>
+                <input
+                    type="text"
+                    id="event-location"
+                    class="form-input"
+                    value={data.location.clone()}
+                    oninput={on_location_input}
+                    placeholder="Enter event location"
+                />
+                <p class="form-help-text">{"Add the location where the event will take place."}</p>
+            </div>
+        </div>
+    }
+}