feat: Update Captain navigation structure (#12761)

# Pull Request Template

## Description

This PR includes an update to the Captain navigation structure.

## Route Structure

```javascript
1. captain_assistants_responses_index    → /captain/:assistantId/faqs
2. captain_assistants_documents_index    → /captain/:assistantId/documents
3. captain_assistants_scenarios_index    → /captain/:assistantId/scenarios
4. captain_assistants_playground_index   → /captain/:assistantId/playground
5. captain_assistants_inboxes_index      → /captain/:assistantId/inboxes
6. captain_tools_index                   → /captain/tools
7. captain_assistants_settings_index     → /captain/:assistantId/settings
8. captain_assistants_guardrails_index   → /captain/:assistantId/settings/guardrails
9. captain_assistants_guidelines_index   → /captain/:assistantId/settings/guidelines
10. captain_assistants_index             → /captain/:navigationPath
```

**How it works:**

1. User clicks sidebar item → Routes to `captain_assistants_index` with
`navigationPath`
2. `AssistantsIndexPage` validates route and gets last active assistant,
if not redirects to assistant create page.
3. Routes to actual page: `/captain/:assistantId/:page`
4. Page loads with correct assistant context

Fixes
https://linear.app/chatwoot/issue/CW-5832/updating-captain-navigation

## Type of change

- [x] New feature (non-breaking change which adds functionality)

## How Has This Been Tested?




## Checklist:

- [x] My code follows the style guidelines of this project
- [x] I have performed a self-review of my code
- [ ] I have commented on my code, particularly in hard-to-understand
areas
- [ ] I have made corresponding changes to the documentation
- [x] My changes generate no new warnings
- [ ] I have added tests that prove my fix is effective or that my
feature works
- [x] New and existing unit tests pass locally with my changes
- [ ] Any dependent changes have been merged and published in downstream
modules

---------

Co-authored-by: Pranav <pranav@chatwoot.com>
Co-authored-by: Sojan Jose <sojan@pepalo.com>

app/javascript/dashboard/components-next/captain/pageComponents/document/DocumentForm.vue

@@ -2,7 +2,7 @@
 import { reactive, computed, ref, nextTick } from 'vue';
 import { useI18n } from 'vue-i18n';
 import { useVuelidate } from '@vuelidate/core';
-import { required, minLength, requiredIf, url } from '@vuelidate/validators';
+import { minLength, requiredIf, url } from '@vuelidate/validators';
 import { useMapGetter } from 'dashboard/composables/store';
 import { useAlert } from 'dashboard/composables';
 
@@ -10,6 +10,13 @@ import Input from 'dashboard/components-next/input/Input.vue';
 import Button from 'dashboard/components-next/button/Button.vue';
 import ComboBox from 'dashboard/components-next/combobox/ComboBox.vue';
 
+const props = defineProps({
+  assistantId: {
+    type: Number,
+    required: true,
+  },
+});
+
 const emit = defineEmits(['submit', 'cancel']);
 
 const MAX_FILE_SIZE = 10 * 1024 * 1024; // 10MB
@@ -18,13 +25,11 @@ const { t } = useI18n();
 
 const formState = {
   uiFlags: useMapGetter('captainDocuments/getUIFlags'),
-  assistants: useMapGetter('captainAssistants/getRecords'),
 };
 
 const initialState = {
   name: '',
   url: '',
-  assistantId: null,
   documentType: 'url',
   pdfFile: null,
 };
@@ -38,19 +43,11 @@ const validationRules = {
     url: requiredIf(() => state.documentType === 'url' && url),
     minLength: requiredIf(() => state.documentType === 'url' && minLength(1)),
   },
-  assistantId: { required },
   pdfFile: {
     required: requiredIf(() => state.documentType === 'pdf'),
   },
 };
 
-const assistantList = computed(() =>
-  formState.assistants.value.map(assistant => ({
-    value: assistant.id,
-    label: assistant.name,
-  }))
-);
-
 const documentTypeOptions = [
   { value: 'url', label: t('CAPTAIN.DOCUMENTS.FORM.TYPE.URL') },
   { value: 'pdf', label: t('CAPTAIN.DOCUMENTS.FORM.TYPE.PDF') },
@@ -70,7 +67,6 @@ const getErrorMessage = (field, errorKey) => {
 
 const formErrors = computed(() => ({
   url: getErrorMessage('url', 'URL'),
-  assistantId: getErrorMessage('assistantId', 'ASSISTANT'),
   pdfFile: getErrorMessage('pdfFile', 'PDF_FILE'),
 }));
 
@@ -106,7 +102,7 @@ const openFileDialog = () => {
 
 const prepareDocumentDetails = () => {
   const formData = new FormData();
-  formData.append('document[assistant_id]', state.assistantId);
+  formData.append('document[assistant_id]', props.assistantId);
 
   if (state.documentType === 'url') {
     formData.append('document[external_link]', state.url);
@@ -218,21 +214,6 @@ const handleSubmit = async () => {
       :placeholder="t('CAPTAIN.DOCUMENTS.FORM.NAME.PLACEHOLDER')"
     />
 
-    <div class="flex flex-col gap-1">
-      <label for="assistant" class="mb-0.5 text-sm font-medium text-n-slate-12">
-        {{ t('CAPTAIN.DOCUMENTS.FORM.ASSISTANT.LABEL') }}
-      </label>
-      <ComboBox
-        id="assistant"
-        v-model="state.assistantId"
-        :options="assistantList"
-        :has-error="!!formErrors.assistantId"
-        :placeholder="t('CAPTAIN.DOCUMENTS.FORM.ASSISTANT.PLACEHOLDER')"
-        class="[&>div>button]:bg-n-alpha-black2"
-        :message="formErrors.assistantId"
-      />
-    </div>
-
     <div class="flex gap-3 justify-between items-center w-full">
       <Button
         type="button"