feat: phase 4 -- wire DirectoryPicker to analyze API + DashboardHome flow (OPE-114)

AddRepoForm.tsx:
- On submit, calls POST /repos/analyze for GitHub URLs
- If large repo (suggestion: 'large_repo'), calls onAnalyzed callback
- If small repo or non-GitHub, proceeds directly to clone+index
- Button shows 'Analyzing...' state with pulse icon during API call
- Graceful fallback: if analyze fails, falls through to direct add

DashboardHome.tsx:
- New state: analyzeResult, pendingGitUrl/Branch, showDirectoryPicker
- handleAnalyzed: opens DirectoryPicker with analyze result
- handleDirectoryConfirm: calls addAndIndex with include_paths
- addAndIndex sends IndexConfig body when include_paths provided
- DirectoryPicker wired with TIER_FUNCTION_LIMITS.free as budget limit

Flow: URL -> Analyze -> Picker (large) -> Clone -> Index (subset)
   or: URL -> Analyze -> Clone -> Index (small, no picker)

Build passes. 194 + 295 + 320 lines across 3 files.

Author: DevanshuNEU

frontend/src/components/AddRepoForm.tsx

@@ -1,9 +1,11 @@
 import { useState } from 'react'
 import { motion, AnimatePresence } from 'framer-motion'
-import { Package, Plus, X, Loader2 } from 'lucide-react'
+import { Package, Plus, X, Loader2, Search } from 'lucide-react'
 import { Button } from '@/components/ui/button'
 import { Input } from '@/components/ui/input'
 import { Label } from '@/components/ui/label'
+import { API_URL } from '@/config/api'
+import type { AnalyzeResult } from '@/types'
 
 // Discriminated union: if isOpen is provided, onOpenChange is required
 type UncontrolledProps = {
@@ -18,21 +20,50 @@ type ControlledProps = {
 
 type AddRepoFormProps = {
   onAdd: (gitUrl: string, branch: string) => Promise<void>
+  onAnalyzed?: (result: AnalyzeResult, gitUrl: string, branch: string) => void
   loading: boolean
 } & (UncontrolledProps | ControlledProps)
 
-export function AddRepoForm({ onAdd, loading, isOpen, onOpenChange }: AddRepoFormProps) {
+export function AddRepoForm({ onAdd, onAnalyzed, loading, isOpen, onOpenChange }: AddRepoFormProps) {
   const [gitUrl, setGitUrl] = useState('')
   const [branch, setBranch] = useState('main')
+  const [analyzing, setAnalyzing] = useState(false)
   const [internalOpen, setInternalOpen] = useState(false)
 
   const isControlled = isOpen !== undefined
   const showForm = isControlled ? isOpen : internalOpen
   const setShowForm = isControlled ? onOpenChange : setInternalOpen
+  const isBusy = loading || analyzing
 
   const handleSubmit = async (e: React.FormEvent) => {
     e.preventDefault()
     if (!gitUrl) return
+
+    // If onAnalyzed provided and URL is GitHub, analyze first
+    if (onAnalyzed && gitUrl.includes('github.com')) {
+      try {
+        setAnalyzing(true)
+        const resp = await fetch(`${API_URL}/repos/analyze`, {
+          method: 'POST',
+          headers: { 'Content-Type': 'application/json' },
+          body: JSON.stringify({ github_url: gitUrl }),
+        })
+        if (resp.ok) {
+          const result: AnalyzeResult = await resp.json()
+          if (result.suggestion === 'large_repo') {
+            onAnalyzed(result, gitUrl, branch)
+            setShowForm(false)
+            return
+          }
+        }
+        // Small repo or non-GitHub: proceed directly
+      } catch {
+        // Analyze failed -- fall through to direct add
+      } finally {
+        setAnalyzing(false)
+      }
+    }
+
     await onAdd(gitUrl, branch)
     setGitUrl('')
     setBranch('main')
@@ -83,7 +114,7 @@ export function AddRepoForm({ onAdd, loading, isOpen, onOpenChange }: AddRepoFor
                 <button
                   onClick={() => setShowForm(false)}
                   className="w-8 h-8 flex items-center justify-center rounded-lg text-muted-foreground hover:text-foreground hover:bg-muted transition-colors"
-                  disabled={loading}
+                  disabled={isBusy}
                 >
                   <X className="w-4 h-4" />
                 </button>
@@ -100,7 +131,7 @@ export function AddRepoForm({ onAdd, loading, isOpen, onOpenChange }: AddRepoFor
                     onChange={(e) => setGitUrl(e.target.value)}
                     placeholder="https://github.com/username/repo"
                     required
-                    disabled={loading}
+                    disabled={isBusy}
                     autoFocus
                   />
                 </div>
@@ -114,7 +145,7 @@ export function AddRepoForm({ onAdd, loading, isOpen, onOpenChange }: AddRepoFor
                     onChange={(e) => setBranch(e.target.value)}
                     placeholder="main"
                     required
-                    disabled={loading}
+                    disabled={isBusy}
                   />
                   <p className="text-xs text-muted-foreground">Repository will be cloned and automatically indexed</p>
                 </div>
@@ -125,17 +156,22 @@ export function AddRepoForm({ onAdd, loading, isOpen, onOpenChange }: AddRepoFor
                     type="button"
                     variant="outline"
                     onClick={() => { setShowForm(false); setGitUrl(''); setBranch('main') }}
-                    disabled={loading}
+                    disabled={isBusy}
                     className="flex-1"
                   >
                     Cancel
                   </Button>
                   <Button
                     type="submit"
-                    disabled={loading}
+                    disabled={isBusy}
                     className="flex-1 bg-primary hover:bg-primary/90 text-primary-foreground"
                   >
-                    {loading ? (
+                    {analyzing ? (
+                      <>
+                        <Search className="w-4 h-4 animate-pulse" />
+                        Analyzing...
+                      </>
+                    ) : loading ? (
                       <>
                         <Loader2 className="w-4 h-4 animate-spin" />
                         Adding...

frontend/src/components/dashboard/DashboardHome.tsx

@@ -12,11 +12,13 @@ import { extractErrorMessage, isUpgradeError } from '../../lib/api-errors'
 import { RepoListView } from './RepoListView'
 import { RepoDetailView } from './RepoDetailView'
 import { AddRepoForm } from '../AddRepoForm'
+import { DirectoryPicker } from '../DirectoryPicker'
 import { GitHubRepoSelector } from '../GitHubRepoSelector'
 import { IndexingProgressModal } from '../IndexingProgressModal'
 import { UpgradeLimitModal } from '../UpgradeLimitModal'
+import { TIER_FUNCTION_LIMITS } from '../../config/api'
 import type { GitHubRepo } from '../../hooks/useGitHubRepos'
-import type { RepoTab } from '../../types'
+import type { AnalyzeResult, RepoTab } from '../../types'
 
 export function DashboardHome() {
   const { session } = useAuth()
@@ -34,6 +36,12 @@ export function DashboardHome() {
   const [indexingRepoName, setIndexingRepoName] = useState('')
   const [showIndexingModal, setShowIndexingModal] = useState(false)
 
+  // directory picker (monorepo subset selection)
+  const [analyzeResult, setAnalyzeResult] = useState<AnalyzeResult | null>(null)
+  const [pendingGitUrl, setPendingGitUrl] = useState('')
+  const [pendingBranch, setPendingBranch] = useState('main')
+  const [showDirectoryPicker, setShowDirectoryPicker] = useState(false)
+
   // upgrade modal
   const [upgradeModal, setUpgradeModal] = useState<{ show: boolean; message: string; repoName?: string }>({
     show: false, message: '',
@@ -54,7 +62,9 @@ export function DashboardHome() {
   }
 
   // shared helper: add a repo and start indexing
-  const addAndIndex = async (name: string, gitUrl: string, branch: string): Promise<string | null> => {
+  const addAndIndex = async (
+    name: string, gitUrl: string, branch: string, includePaths?: string[],
+  ): Promise<string | null> => {
     const response = await fetch(`${API_URL}/repos`, {
       method: 'POST',
       headers: { Authorization: `Bearer ${session?.access_token}`, 'Content-Type': 'application/json' },
@@ -70,9 +80,17 @@ export function DashboardHome() {
     const data = await response.json()
     if (!data.repo_id) throw new Error('Missing repo_id in response')
 
+    const indexBody = includePaths
+      ? { include_paths: includePaths, incremental: false }
+      : undefined
+
     const indexResponse = await fetch(`${API_URL}/repos/${data.repo_id}/index/async`, {
       method: 'POST',
-      headers: { Authorization: `Bearer ${session?.access_token}` },
+      headers: {
+        Authorization: `Bearer ${session?.access_token}`,
+        ...(indexBody ? { 'Content-Type': 'application/json' } : {}),
+      },
+      ...(indexBody ? { body: JSON.stringify(indexBody) } : {}),
     })
 
     if (!indexResponse.ok) {
@@ -160,6 +178,38 @@ export function DashboardHome() {
     }
   }
 
+  // When AddRepoForm detects a large repo, show the directory picker
+  const handleAnalyzed = (result: AnalyzeResult, gitUrl: string, branch: string) => {
+    setAnalyzeResult(result)
+    setPendingGitUrl(gitUrl)
+    setPendingBranch(branch)
+    setShowDirectoryPicker(true)
+  }
+
+  // User selected directories in the picker -- clone and index with subset
+  const handleDirectoryConfirm = async (selectedPaths: string[]) => {
+    if (!analyzeResult) return
+    try {
+      setLoading(true)
+      const name = analyzeResult.repo
+      const repoId = await addAndIndex(name, pendingGitUrl, pendingBranch, selectedPaths)
+      setShowDirectoryPicker(false)
+      setAnalyzeResult(null)
+      if (repoId) {
+        setIndexingRepoId(repoId)
+        setIndexingRepoName(name)
+        setShowIndexingModal(true)
+      }
+      refreshRepos()
+    } catch (error) {
+      toast.error('Failed to add repository', {
+        description: error instanceof Error ? error.message : 'Please try again',
+      })
+    } finally {
+      setLoading(false)
+    }
+  }
+
   const selectedRepoData = repos.find((r) => r.id === selectedRepo)
   const isRepoView = selectedRepo && selectedRepoData
 
@@ -193,11 +243,23 @@ export function DashboardHome() {
 
       <AddRepoForm
         onAdd={handleAddRepo}
+        onAnalyzed={handleAnalyzed}
         loading={loading}
         isOpen={showAddForm}
         onOpenChange={setShowAddForm}
       />
 
+      {analyzeResult && (
+        <DirectoryPicker
+          isOpen={showDirectoryPicker}
+          onClose={() => { setShowDirectoryPicker(false); setAnalyzeResult(null) }}
+          repoInfo={analyzeResult}
+          onConfirm={handleDirectoryConfirm}
+          loading={loading}
+          functionLimit={TIER_FUNCTION_LIMITS.free}
+        />
+      )}
+
       <IndexingProgressModal
         repoId={indexingRepoId}
         repoName={indexingRepoName}